I don't see why we would need to change anything. You can't tell what sex a rabbit is in the wild just by looking at it unless of course you pick it up and investigate further. They don't have longer eye lashes or anything like that. Besides if we go with fothers suit idea with the zipper then it's just a suit anyways no need to be male or female IMO.
Anyways I think the sprite is pretty much finished for now. As I am pretty happy with it myself and don't see many other changes that can be made at this point. But if you would like to attempt to make it look more feminine be my guest. But you should use the bunny3.png with the corrected feet and better basket etc.
