You are simply describing it as a lategame land/useless spell sink for aggro decks and I think there simply are way better garbage sinks, even for aggro decks, like XR Burn spells or looting/rummaging effects.
Deep Analysis nowadays is a pretty bad card draw spell IMO, unless you discard/mill it. I do think the Cannon is actually a decent discard outlet. I've recently added a madness theme to test it and for discard outlets I mostly had some criteria to work well with madness, which was either having a great upside or being as cheap as possible, because the mana advantage or a reckless wurm through madness isn't worth much if you have to pay 2-3 mana for discarding it. The fact ythat you can only use it once per turn isn't really a downside in that regard, since you will barely be able to play multiple mandess cards in one turn and the fact that it's repeatable is quite nice. Again I think that cards like Deep Analysis belong in the category of madness cards or rather cards which profit from discarding.
Who plays Razortip Whip? Viridian Longbow is mostly there to be used against creatures. I think the best comparisons for that purpose would be Thermo Alchemist and Ill-Gotten Inheritance, which are booth miles better if you only look for ways to kill the opponent with noncombat damage.
Pauper Cube & Artifact Pauper Cube & Multiplayer Cube
Interested in building your own Pauper Cube? Take a look at some of the lists and the following project: The "Evaluate Everything" Project (updated to M21/JMP)
Deep Analysis nowadays is a pretty bad card draw spell IMO, unless you discard/mill it. I do think the Cannon is actually a decent discard outlet. I've recently added a madness theme to test it and for discard outlets I mostly had some criteria to work well with madness, which was either having a great upside or being as cheap as possible, because the mana advantage or a reckless wurm through madness isn't worth much if you have to pay 2-3 mana for discarding it. The fact ythat you can only use it once per turn isn't really a downside in that regard, since you will barely be able to play multiple mandess cards in one turn and the fact that it's repeatable is quite nice. Again I think that cards like Deep Analysis belong in the category of madness cards or rather cards which profit from discarding.
Who plays Razortip Whip? Viridian Longbow is mostly there to be used against creatures. I think the best comparisons for that purpose would be Thermo Alchemist and Ill-Gotten Inheritance, which are booth miles better if you only look for ways to kill the opponent with noncombat damage.
Pauper Cube & Artifact Pauper Cube & Multiplayer Cube
Interested in building your own Pauper Cube? Take a look at some of the lists and the following project: The "Evaluate Everything" Project (updated to M21/JMP)