Nice tank. If you add the driftwood you want, it would add a neat contrast to the sand. Hairgrass will look terrific.
It seems like cats just love to be on top of the tank. I've seen at least a dozen pictures of tanks with cats on the hood. Even my LFS has a cat that does in every hooded tank in the store. Does yours also drink from the tank Amanda? Most cats think AquaClears are their private water trough.