Like it a lot - was looking to make a pauper deck, and i don't often play blue, you've inspired me sir
A bit expensive for a Pauper, and it seems to take several turns of being open before you can do much. You seem to be pretty much forced to use the counter-spells on the opponent's opening moves and not have them available for use on stronger drops. I'd have to try it out first hand outside of of playtesting to say for sure, but it seems there aren't enough low-cost drops to use turn 1-4 until you can afford to put out tapped lands in place of the Ninjas. There's always Phantasmal Bear and the Phy-Manas, Vault Skirge and Porcelain Legionnaire being the most obvious and having the additional benefit of making use of your double mana lands if they get drawn later instead.