1. Proxy commands - It would be really cool if you could tell your Proxies to do stuff! I want to be able to tell proxies to follow me or go after a flag carrier or defend key locations. It would also be cool if you could also do this while controlling a SpyProxy. You could tell other Proxies to follow your SpyProxy so that you can "control" several Proxies at a time. It would be really funny to see Proxies running around with flags (although they probably shouldn't be able to score goals)
2. Proxies and weapon pickups - I think it would also be fun if we could get Proxies to dismantle pickups use them to increase their power! It should require 6 Proxies to do this, and the results for certain pickups should be as follows:
A. Rockets and AVRiL rounds: Proxies strap them on to themselves as makeshift jetpacks. When they spot an enemy, they activate them and rocket themselves towards the enemy, homing in until BOOM!
B. Needleballs: NeedleProxies!
C. Standard and Epic's Sticky grenades: Bigger explosion.
D. Special Grenades: Gives Proxies Napalm/Poison/Disruptor abilities.
E. C.U.T.T.E.R. Blades: Blades and blade shards fly out when the Proxy detonates.
F. MUG ammo: Proxies trail fire/ice wherever they go and explode in a(n) fire/ice ball/cloud.
G. Shock rifle ammo: Big Shock Combo blast upon detonation.
H. Lightning gun ammo: Lightning bolts damage nearby players upon detonation.
I. Flak Shells: Flak ball explosion.
J. Link Charges: Damaging Plasma cloud:
K. Spider Mines: Spider Proxies!
L. BioSludge: Goop splatter.
M. Fire Mines: ?
N. Minigun Rounds, Sniper, Assault Rifle, CPP, etc.: Proxies turn themselves into big, hopping, explosive bullets that shoot themselves at enemies!
O. Proxy pickups: We're FREE!!!!! The freed Proxies join your motley gang.
P. Arrows: Proxies arm themselves with mini-crossbows and shoot quarrels at enemies for less damage.
P. Redeemer and Gravity Vortex:

Q. Turret beacons: Proxy Turrets?
This can all be done via the command system mentioned above, or Proxies can just pick them up by themselves if they want to.
(Yeah, it does sound overpowered, doesn't it)