Keyboard works fine, there is so much space left inside that you could easily have 4-5 raspberries with a self powered hub with HDD and SSD etc...
You get the idea. 
4-5 Pi's??!?!?!?
you could have a nice little cluster going and have each one doing a designated task. Like one for a minecraft sever, one as a web server, one to do business and so on lol. You could just remote terminal each one and get it to do the tasks.
That sound awesome in it's self.