Beware, this post contains excessive rambling.
EXACTLY, a realistic flight system (like in spore minus the flapping limit, so you'd have to MAINTAIN it) would be GREAT with realistic wings, and wing meshes are relatively easy to find and make, too. it'd be nice to have some realistic wings (meaning tucked against the sides, as well, not being constantly held up) absolutely amazing, and i've seen very few games pose wings like that (the only one, actually, being Istaria with it's Dragon wings) the results are beautiful, too. with the right animations, the wings could look amazing. however, please texture bat/dragon and feather wings on SEPARATE meshes, they do not function the same because wing bones on avian wings are far different than bat-like wings, that have individual fingers as to where on Avian wings it's a few bones and the flexibility is limited (not to mention, it'd be harder to fly with the lift from Avian wings because it wouldn't produce enough upward force to sustain flight on a wolf or lion unless the wings were big enough, which would affect balance and maneuverability as well as flight speed.)
Feel free to correct this below, da?