I second what Shiro said and while I do fear it may invite swarms of "warrior kitties" it would make creating lynx, servals, and other wild but still small cats much easier.
Also, I want to add that one small factor that can make maps more interesting is the slightest "human" touch. No, I don't mean make full-up cities, but throwing a simple house in (like the ones we currently have in crater or paradise) would be nice. Windmills [like in Paradise], fences are something seldom seen in the IT-servers. There doesn't need to be a rhyme or reason for them to be there so long as they're nicely placed. They make for good RP fodder for Rpers, and a "different" kind of perch for chatters.
Another thing, more caves please? Both normal and dark? Two-stories? [It is possible to make 2-storied caves, I've done it before.] Having the different biomes are nice but more fantasy based maps add variety [like Crystal Forest]