card:Sage's Row Denizen might be up your alley for this.
card:Rogue's Passage is thrifty, but expensive, especially to be used every turn. Plus, for the number of dual lands you're running (4 of both shock/tap, and 2 guildgates) having more colorless symbols might not be the best choice. I would suggest Artful Dodge to have an instant access to unblockable.
Speaking of Consuming Aberration , you should try running four.
All in all, I really dig this. Dimir is stupid powerful right now and nobody is really checking it because they're obsessed with Red and Esper. Be cautious that you won't get outsped by Red, though.