Overall I think it looks like a really nice deck and I have only a few suggestions, namely: Dream Fracture similar to arcane denial but trades a card to them for a mana. The card is much better then you get to duels (where arcane denial is problematic). foil - free counter spell! You have some number of ways to get islands into hand, like drawing one dirctly, reach, cultivate or bouncing one with a bounce land (the latter will likely get fetched with the general land fetches you are running), so it should be fairly easy to play for free and then you get to reuse the cards discarded to foil. stinkweed imp - it will typically come down, get traded and then dredged back (or prevent others from attacking you at all, which is even better). On average I think you will likely dredge less than 2 non-permanents per time (it is only straightforward if you do not take to many things into account, like that you need 3 mana to play it, it needs to die and so on, and the tutors make it hard to say exactly how many sorceries and instants compared to everything else are left at that point).
Have you considered running looters? E.g. Looter il-kor, it seems fairly strong with your commander (they also happen to be redicules with stinkweed imp).
Ohh, also, I think Mnemonic wall is better than scrivener (not necessarily in a 1 vs 1 comparison, but mainly in that the other return wizards have similar stats and 0/4 can sometimes be more usefull than 2/2 - e.g. for blocking 3/3) - you already have 2 better return wizards for the wizard tutor anyway
Dream Fracture similar to arcane denial but trades a card to them for a mana. The card is much better then you get to duels (where arcane denial is problematic).
foil - free counter spell! You have some number of ways to get islands into hand, like drawing one dirctly, reach, cultivate or bouncing one with a bounce land (the latter will likely get fetched with the general land fetches you are running), so it should be fairly easy to play for free and then you get to reuse the cards discarded to foil.
stinkweed imp - it will typically come down, get traded and then dredged back (or prevent others from attacking you at all, which is even better). On average I think you will likely dredge less than 2 non-permanents per time (it is only straightforward if you do not take to many things into account, like that you need 3 mana to play it, it needs to die and so on, and the tutors make it hard to say exactly how many sorceries and instants compared to everything else are left at that point).
Have you considered running looters? E.g. Looter il-kor, it seems fairly strong with your commander (they also happen to be redicules with stinkweed imp).
Ohh, also, I think Mnemonic wall is better than scrivener (not necessarily in a 1 vs 1 comparison, but mainly in that the other return wizards have similar stats and 0/4 can sometimes be more usefull than 2/2 - e.g. for blocking 3/3) - you already have 2 better return wizards for the wizard tutor anyway