Codex Shredder is great against scry. When they keep the cards they scry, Shred it. After about 2 or 3 times, they try to fool you and leave something they don't want on top, so stop for a few minutes, then go back to it. Keep them guessing.

I agree with DMRxITxUP about the consistency. Yes, you need functionality, but you should try to maximize those functions with repetition, not random variety. Anything that can make a huge difference should be maximized.

I also agree with -Logician about removing the unnecessary creature cards. Sage's Row Denizen , Slate Street Ruffian , Syndicate Enforcer , Gutter Skulk , Horror of the Dim - none of these help toward accomplishing the Mill win condition.

Max our cards like Doorkeeper to mill and Wall of Frost to stall the board. Bump up to 4x of Pilfered Plans , Psychic Strike , Tome Scour , Breaking / Entering , and Mind Grind . This gives you room for about 8 more cards to make 36 spells, giving room for 24 lands.