Well, there's always just straight
Bunny / Bunnie, but that definitely seems more nickname-y.
UsagiJack (as in Jackrabbit?)
Molada, the Kannada word for rabbit, could possibly make a nice name.
...Hm. That's all I got. ^^; There really aren't many names meaning rabbit, are there? Maybe
Sylvia after the genus Sylvilagus? Or Sylvila, I suppose.