One thing that is impressive is that the National Zoo ties strips of wood to the trees so that the big cats can stretch themselves out and claw the trunks without damaging the real trees underneath. I wish that more zoos would use that approach and therefore avoid the usage of hotwire.
Hmm, I think this enclosure could be noticeably improved if they cut down on the moat, to the point that it was just a pond. Perhaps a tall fence with plexiglass windows could be raised around it.