Personally, I like the idea of additional mounts. Originally I was more for multiple chocobos - and in a way, I still am. I like the idea of non-chocobo mounts. I still, however, think chocobos should have advantages. Not standard chocobos, but bred ones. I think that when you breed chocobos, you should be able to get faster ones. All the "glamour mounts" should be there for laughs and showing off, basically when you're just messing about. Chocobos that are bred by the individual should be marginally faster depending on the quality of your breeding. Perhaps have stamina/speed/boost, like in chocobo racing?
As for non-chocobo options, I like the goobbue because I find it a good laugh when you're being intentionally silly. I don't think we should have any other mounts so large, though! A dodo mount would be nice, and a large moomba could make for an effective mount. Obviously the goats could work, too, although they would have to be slower (I imagine). Drakes would be nice for a flying mount.