Hi, have you tried woodpellet cat litter in her litter tray? I found as it is heavy it doesn't get kicked out as bunny hops in and out of the tray. Then I would put hay on top of it or at one end of the tray. You can use vet bed for a bed, although my rabbit used to like to sleep on the floor in the middle of the room!
I hope you don't mind me saying but most indoor cages are very small and only suitable to use as a base really I didn't use a cage for my rabbit, I rabbit proofed a room and he lived free range in there.