Sounds great, but there are certain things you should probably ban in order to make it more fun and perhaps a bit safer.
1) No RF interference.
2) No untethered projectiles.
3) No explosives.
4) If you allow flame weapons, no projected liquids. Flamethrowers need to be a gas. Propane preferably. No more than 4oz of fuel on board for the flamerthrower. This also goes for combustion engine bots.
5) No EMP or electrostatic discharge.
6) Generally no liquid discharge of any kind such as oil, adhesives, etc.
7) Ropes and netting can be a real pain in the butt and spoil the fun, you might want to consider banning those too.
8) Vaulting into the air should be allowed (it's quite fun) but you might want to avoid actual flight.
Enclosing your fight area in 1/4" Lexan will do for small machines, but bigger ones will need 1/2".