Yeah... I guess we are only really missing walls right now for underwater campaigns. I guess you could do a "just swim and swim and swimswimswim!" campaign (who ever heard of walls underwater, anyway?

) but it would be better to at least have coral or seaweed or something to make the underwater wilderness look more interesting...
Another thing that would be nice are more sprites/small pics (manikus has made a few of the latter); but these take longer than icons, so...