iPad Orchestra Update

So the iPad orchestra project is underway and I get more excited about it by the day. Here's the model I am looking at.
I'm getting 10 splitter boxes made, each able to take up to 5 iPad connections. Each box will represent a 'section' in the orchestra. So we could have 10 different instruments or apps. eg
1x strings, 2x guitars, 1x bass, 3x percussion, 2x piano/keyboard/synth, 1x lead instrument
Each section can take up to 5 players so we could have up to 50 children playing at any one time.
Each box has a single line output which will feed directly to a 10 track mixer that we have at school. This will mean that we can mix the sound to get levels absolutely right. Really interested in finding quality and simple music apps. Here's what I have so far:

6 Strings - an excellent guitar and stringed instrument app.
Drums! - Beautiful sounding drums with a choice of three kits.
Percussive - Again, beautiful sample sounds of tuned percussion

If you know any more let me know!

More to follow!