Bottom line is, just like in the Parks, you can't see everything.
They've initiated "StagePass". If you get those, it guarantees you a seat in one early and one late presentation in the 2 smaller venues.
There is concurrent and overlapping programming that helps spread out the crowd (another reason you can't do everything). They had this for 2009, but not so much for 2011.
Right now I'm about 15 people from the front of the line for a presentation about the voices of Buena Vista Street. I already have a StagePass for the Once Upon a Time presentation and I got a free Disney Infinity figure...granted, I was on the show floor right at 9am.
If you choose to do any of the Arena presentations, it's a big time commitment.