Did you know, I prefer just a Chocobo/dragon system. Too many mounts and it just becomes cheesey.

Too much variety and it impinges on the artistic style of the universe.

Have you ever seen one of those Predator Vs. Alien movies? Or a Ninja Vs. Alien movie? That is what happens when you throw everything but the kitchen sink at the audience. It's just not pretty.

Restraint is sometimes necessary when creating a gameworld.