It goes quite against my experience that you say that bird wings require “only a few joints” and dragon/bat wigns full arm with hand bones. Birds have a very similar underlying anatomy as bats. In fact, youd even need more bones for a good looking bird wing rig than for a bat. You have to control all those feathers after all. Anyway, about a year ago I developed a wing rig for bird wings, but you can also transfer that to a bat/dragon rig with some different skinning and less inbetween bones. Check it out, maybe you find it useful:
