This will be our third year to stay at All Star Music and we've stayed in Calypso the past two years with plans to do it again this November.
Being close to Melody Hall is the only perk you get for your extra $10, but well worth it especially after a long day and you're getting back late. The AllStar building are pretty well spread out and unless you're in Calypso it can be about 1/4 mile hike back to the room from the bus stop.
One thing I might note for you to consider when you make requests. We had a ground floor room facing the pool in 2004 and the maintanence crews start the pressure washers every morning at the first hint of dawn to clean around the pool decking. That can interrupt your snooze time if you're planning to sleep in late. Last year we opted for a room on an upper level on the backside of Calypso and found that was much easier for transporting luggage to our vehicle, yet we were still right up by Melody Hall for the morningswhen we wanted to use the busses.
As far as the crowds are concerned, All Star Music tends to be quieter and less heavily trafficked than Movies or Sports. And if you plan to visit the other pools, Music has you in the center of all the buildings with less walking from one resort to the other.