Looking for feedback for my first cube

Well, here's the link to my cube :

http://www.cubetutor.com/viewcube/78211

Some things to consider first

• This is my first attempt at a cube ever. I'm doing it mainly to have a way to play some games with friends that stopped playing magic some time ago, but are positive to the idea of sitting down to play a couple games.

• The idea behind is to encourage people to draft a Ravnica guild, without being too extreme on the ravnica-specific card selection. My goal is for the draft to have a soft Ravnica theme, without giving up more powerful/fun cards.

• Having said that, card choices were made based on what i already had, since my budget is tight.

  I'm looking for any kind of feedback from more experienced people, regarding everything. As i said i have zero cube experience so far, so any and all advice are welcome. Thanks for your time!