Superfriends!!!

Contagion Clasp and Contagion Engine? Especially the latter, it functions as really good removal as well! Maybe other Proliferate spells also? Tezzeret's Gambit is pretty sweet, and I'm a big fan of Volt Charge.

Yeah dude holy crap, Inexorable Tide, Steady Progress, Thrummingbird?!?!? I'm pretty sure only about 5 of the 15-ish Proliferate cards are NOT beneficial to this deck. There's removal, counters, geez. Check 'em out for sure!