I"m not so sure that Frontier would give us a fish or (flying)bird rig if they're only going to do one animal out of it. Tools for mods wise it would be fantastic, but from a coding standpoint I'm just can't see putting that effort into something that would have all new, all different behaviors, animations and design all for one animal, when it could be used for so much more.
Think about it this way, I'll use the giraffe and platypus as two animals that almost certainly have completely unique rigs. outside of a second giraffe I can't see another animal come out of the giraffe rig, and certainly nothing for the platypus.
Meanwhile, you get a fish and a flying bird, when it could be used hundreds of times over again, but you just stopped with one possibility. I don't mean that I would expect hundreds of birds of fish, but getting only one would be kind of weird.
