You must include certain animations
walk
run
idle
death
as these seem to be hard coded to the engine and you'll get really weird behaviour without them.
If you make one set of weapon holding animations you can use them for all weapon types, although it might look a bit funny having your character firing a bazooka from the hip!
Custom animations without the biped are quite buggy. Ive just started to try recently and its taking alot of effort to get right!
peace
butters
PS. Bond, If you did add geometry and bones for the hair, it could be a really useful biped for other characters.... samurais with ponytails, aliens with tenacles comin from their heads etc
"It's often better to keep your mouth shut and let people think you're an idiot, than to open it and confirm their suspisions" - Noel Coward