Detain Them: First Deck, UW looking for feedback

I recently started getting into Magic after some Peer pressure from my friends. After a lots, and -lots- of editing, I've finally finished a deck with a couple of playtests.

http://deckbox.org/sets/526940

I would love to get some feedback on this, maybe some suggestions on cards to get, cards to remove, basically how to tune up this deck. In my playtests, I noticed I struggled during the mid to end game, so some pointers there would be helpful.