As a disclaimer, my only experience in playing Mono-Blue Tempo is from Standard, and I often thought about what Mono-Blue Delver would look like if I had simply traded out the functional one-drops for Delver of Secrets, hence the list I've been tinkering with.
I think that Curious Obsession is a solid card and does replace at least some can-trips in the deck. Getting an Obsession on a 1 drop creature is incredibly powerful and gets even better with Modern's card pool. I realized that I don't have access to Snapcasters like I thought I did (must have sold them a while ago or traded them in?), so I need to tweak the list again anyways.
I see your logic with Disrupting Shoal. Perhaps a mix of Shoals and the newly printed Force of Negation is worthwhile? The scarier plays that we could see on T1 are almost all non-creature spells, generally speaking, so I do think that Force has a place in the format.
The Merfolk Tricksters are an experiment to see if they function as pseudo-removal spells; sometimes, we only need a creature to be tapped down in order to gain the Tempo needed to win. It may be that Cryptic Serpent is the better creature? A 6/5 is no joke and eats most of the relevant creatures across the other side of the field. It's essentially a removal spell that can get in for 2-4 points of damage normally, which is just enough to cross the finish line most of the time. Tapping down a flying blocker at the end step to get tempo with a live Delver, Pteramander, or Djinn seems really good. It also functions as an acceptable chump blocker when it needs to to buy more time.
I like that Tempest Djinn has high enough toughness and the right keyword to block a majority of the creatures in the format and gets better as the game goes long, so I think it should be a decent budget replacement of Thing in the Ice. It stonewalls Arclight Phoenix well and pressures life totals in large chunks when you've got Tempo control.
The super budget list that I'll be working from will look something more like this:
Do note that this deck is mainly for kitchen table play with the occasional foray into a Modern tournament when time allows. I'm superstitious about playing 61 card decks, and I think the addition of more cantrips and the Sandbars will likely help smooth out any mana problems that may occur, both with flooding and in preventing mana screw. I hear the criticisms about Obsession, but I think that it's underrated currently
tricksters are solid cards and very good against creature heavy decks
the main advantage of serpent over djinn is being push proof, push is now the third most common removals spell in modern and being resistant to it is a big deal, the second main advantage is that its can take out huge goyfs, gurmags and make most death shadows pause, yes djinn can block a phoenix, but phoenix's are rarly the issue in that matchup, the big issue tends to be thing in the ice.
curious obsession, i think this is a straight up bad card for the deck, the reason it works in standard is the 12-16 one drops to equip it to and a load of defensive spells and lots of two mana removal, modern is different most modern removal is on mana, and unlike in standard where mono u flyers is one of the more aggressive end of things this is much less so. i think that's where the bug differences in card choices have come from, this is at its core a spell slinger tempo deck where as the standard is a creature disruption tempo deck, decks like fairies/rogues/u/w flyers are much more sued to a creature enchantment, delver and pteramander bother need the spell slinging to work and i feel curios takes away from the decks synagis for a maybe card draw and a not very impactful pump
spell slinging tempo needs to spend turns 2-3 stopping our opponents game plan and threats as otherwise we don't get a turn 4, we are nowhere near fast enough to race, and if we try we lose, the decks is already on the bad side of 2-1s with shoal and now force we simply cannot afford the 2-1 we take from an opponent pushing a our delver turn 2 when we tap to play curiosity or have our stuff blocked by a well timed rattle chains. it's also using up a mana turn 2 which we need for remands or cantrips to find our next counter/land and make our serpent and ptermander cheaper and help our delver.
the last issue for me with obsession is that its taking up the slot for serum visions and disruption, visions has 2 major roles in the deck, first its adding another cantriping soc that we can see with delver, and to reduce costs for serpent and ptermander. secondly it's the only card in the decks that allows you to manipulate the top of your deck which makes delvers ability to flip vastly more consistent.
and like i said above if we are not disrupting our opponent we often don't get to turn 3, solid removal and 1 mana counter magic is extremely important (you never have to deal with phonixs if you can consistently stop there faithless lootings.)
now with the new free counter spell djinn may be better and workable in the deck
other creatures that have been tried and not quite worked in the past include
merfolk trickster (our closest thing to a budget snap caster in function we have)
curios homunculus (this dude is a personal favorite as hes a very constant turn 3 flip and he dose wonders when cryptic and chart a course where both 3 of mb)
spellstutter sprite (with the meta speeding up and more and more onedrops being played sprite may be worth another look (may work well in a deck with obsession as it provides another body to work with)
Illusory Angel (most similar to djinn but can be played in decks with utility lands much easier but struggles to come down late game (she really needed flash))
Venser, Shaper Savant(really good for a turn or 2 but no evasion can be a bit lacking)
Nimble Obstructionist (not half bad, one of the best choices if not running clique)
less budget
Jace, Vryn's Prodigy (very very good in gainst control)
Thing in the Ice (used to be budget, now no longer so)
sb looks like a solid start
i highly recommend 2-3 copies of Ceremonious Rejection. is a extremely solid card against tron and all versions of affinity, it used to be a 4 of sb when kci was around but is still good enough against the others and sb tec (like relics bridges and chalices) that's its still a priority.
Spell Snare is very very good against particular decks and because of its reprint in battle bond is still sitting under $1 so well worth 2 of sb
i highly recommend 2 Dismember is your 75, it provides a way to deal with big threats that you would otherwise struggle to keep off the board
boomarang is nice Echoing Truth or repeal can sometimes be better (depends on your meta)
Hurkyl's Recall is fantastic at making affinity cry (less useful now but still one of the best source of artifact hate in modern)
Dispel for counter wars against control.
shadow of doubt is an awesome sb option in the current meta as either just stopping a fetch (against deathshadow) to stopping cord of calling/ whir of invention/ gifts ungiven. its also one of the best ways to stop titan shift decks.
i really think you need some gy hate, on a budget im a fan of tormod's crypt, although nihil spellbomb and ravenous trap will both also work very well.
without thing in the ice or cryptic commands the deck really struggles to deal with go wide strategies, the best option i've found is engulf the shores (although there is a case for sleep and Whelming Wave in a deck that runs 4 serpents)
I think that Curious Obsession is a solid card and does replace at least some can-trips in the deck. Getting an Obsession on a 1 drop creature is incredibly powerful and gets even better with Modern's card pool. I realized that I don't have access to Snapcasters like I thought I did (must have sold them a while ago or traded them in?), so I need to tweak the list again anyways.
I see your logic with Disrupting Shoal. Perhaps a mix of Shoals and the newly printed Force of Negation is worthwhile? The scarier plays that we could see on T1 are almost all non-creature spells, generally speaking, so I do think that Force has a place in the format.
I think that Archmage's Charm is going to steal more permanents than initially thought. Snagging Champion of the Parish, Death's Shadow, Goblin Guide, Noble Hierarch, and Aether Vial are all legitimate targets for the Charm and are pretty swingy plays.
The Merfolk Tricksters are an experiment to see if they function as pseudo-removal spells; sometimes, we only need a creature to be tapped down in order to gain the Tempo needed to win. It may be that Cryptic Serpent is the better creature? A 6/5 is no joke and eats most of the relevant creatures across the other side of the field. It's essentially a removal spell that can get in for 2-4 points of damage normally, which is just enough to cross the finish line most of the time. Tapping down a flying blocker at the end step to get tempo with a live Delver, Pteramander, or Djinn seems really good. It also functions as an acceptable chump blocker when it needs to to buy more time.
I like that Tempest Djinn has high enough toughness and the right keyword to block a majority of the creatures in the format and gets better as the game goes long, so I think it should be a decent budget replacement of Thing in the Ice. It stonewalls Arclight Phoenix well and pressures life totals in large chunks when you've got Tempo control.
The super budget list that I'll be working from will look something more like this:
4x Delver of Secrets
4x Pteramander
3x Merfolk Trickster
4x Tempest Djinn
Instants (24)
4x Vapor Snag
4x Thought Scour
3x Serum Visions
4x Remand
3x Disrupting Shoal
2x Force of Negation
4x Archmage's Charm
4x Curious Obsession
Lands (18)
2x Field of Ruin
14x Island
2x Lonely Sandbar
4x Flashfreeze
2x Entrancing Melody
4x Mistcaller
3x Boomerang
2x Spell Pierce
Do note that this deck is mainly for kitchen table play with the occasional foray into a Modern tournament when time allows. I'm superstitious about playing 61 card decks, and I think the addition of more cantrips and the Sandbars will likely help smooth out any mana problems that may occur, both with flooding and in preventing mana screw. I hear the criticisms about Obsession, but I think that it's underrated currently
UB Dralnu, Lich Lord
RBW [Primer]-Kaalia of the Vast
BUG [Primer]-Tasigur, the Golden Fang
GWU [Primer]-Arcades, the Strategist
WUB Primer-Aminatou, the Fateshifter
UBR Nicol Bolas, the Ravager
the main advantage of serpent over djinn is being push proof, push is now the third most common removals spell in modern and being resistant to it is a big deal, the second main advantage is that its can take out huge goyfs, gurmags and make most death shadows pause, yes djinn can block a phoenix, but phoenix's are rarly the issue in that matchup, the big issue tends to be thing in the ice.
curious obsession, i think this is a straight up bad card for the deck, the reason it works in standard is the 12-16 one drops to equip it to and a load of defensive spells and lots of two mana removal, modern is different most modern removal is on mana, and unlike in standard where mono u flyers is one of the more aggressive end of things this is much less so. i think that's where the bug differences in card choices have come from, this is at its core a spell slinger tempo deck where as the standard is a creature disruption tempo deck, decks like fairies/rogues/u/w flyers are much more sued to a creature enchantment, delver and pteramander bother need the spell slinging to work and i feel curios takes away from the decks synagis for a maybe card draw and a not very impactful pump
spell slinging tempo needs to spend turns 2-3 stopping our opponents game plan and threats as otherwise we don't get a turn 4, we are nowhere near fast enough to race, and if we try we lose, the decks is already on the bad side of 2-1s with shoal and now force we simply cannot afford the 2-1 we take from an opponent pushing a our delver turn 2 when we tap to play curiosity or have our stuff blocked by a well timed rattle chains. it's also using up a mana turn 2 which we need for remands or cantrips to find our next counter/land and make our serpent and ptermander cheaper and help our delver.
the last issue for me with obsession is that its taking up the slot for serum visions and disruption, visions has 2 major roles in the deck, first its adding another cantriping soc that we can see with delver, and to reduce costs for serpent and ptermander. secondly it's the only card in the decks that allows you to manipulate the top of your deck which makes delvers ability to flip vastly more consistent.
and like i said above if we are not disrupting our opponent we often don't get to turn 3, solid removal and 1 mana counter magic is extremely important (you never have to deal with phonixs if you can consistently stop there faithless lootings.)
now with the new free counter spell djinn may be better and workable in the deck
other creatures that have been tried and not quite worked in the past include
merfolk trickster (our closest thing to a budget snap caster in function we have)
curios homunculus (this dude is a personal favorite as hes a very constant turn 3 flip and he dose wonders when cryptic and chart a course where both 3 of mb)
spellstutter sprite (with the meta speeding up and more and more onedrops being played sprite may be worth another look (may work well in a deck with obsession as it provides another body to work with)
Illusory Angel (most similar to djinn but can be played in decks with utility lands much easier but struggles to come down late game (she really needed flash))
Venser, Shaper Savant(really good for a turn or 2 but no evasion can be a bit lacking)
Nimble Obstructionist (not half bad, one of the best choices if not running clique)
less budget
Jace, Vryn's Prodigy (very very good in gainst control)
Thing in the Ice (used to be budget, now no longer so)
sb looks like a solid start
i highly recommend 2-3 copies of Ceremonious Rejection. is a extremely solid card against tron and all versions of affinity, it used to be a 4 of sb when kci was around but is still good enough against the others and sb tec (like relics bridges and chalices) that's its still a priority.
Spell Snare is very very good against particular decks and because of its reprint in battle bond is still sitting under $1 so well worth 2 of sb
i highly recommend 2 Dismember is your 75, it provides a way to deal with big threats that you would otherwise struggle to keep off the board
boomarang is nice Echoing Truth or repeal can sometimes be better (depends on your meta)
Hurkyl's Recall is fantastic at making affinity cry (less useful now but still one of the best source of artifact hate in modern)
Dispel for counter wars against control.
shadow of doubt is an awesome sb option in the current meta as either just stopping a fetch (against deathshadow) to stopping cord of calling/ whir of invention/ gifts ungiven. its also one of the best ways to stop titan shift decks.
i really think you need some gy hate, on a budget im a fan of tormod's crypt, although nihil spellbomb and ravenous trap will both also work very well.
without thing in the ice or cryptic commands the deck really struggles to deal with go wide strategies, the best option i've found is engulf the shores (although there is a case for sleep and Whelming Wave in a deck that runs 4 serpents)
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