Werebears should probably have their own animations anyway (in which case this wouldn't be a problem).
It's low priority atm, but the Skyrim project will be making a werebear (and wereboar) later, we've got 2 animators and a few modellers, so perhaps we could help you out later. :deal:
For now though, about the camera movement, if you want to try it out, edit the x.nif, not the .nif, these are only used for previewing and importing as far as I can tell.
What you see in game is a combination of the x.nif and x.kf files, so you edit these to get an effect in game.
There
might be problems with usng this method to make the player look larger though, for example, the camera doesn't collide AFAIK, so the player might find himself walking through ceilings. :shrug: