I remember watching shooting stars in IT. And it was night :3 It was beautiful to watch, even though it lasted only for a couple seconds that I was there.
Back on Topic:
Tree climbing would be awesome, but I'm not sure how that would work or anything. I'm not a big coder/programmer, but I'd say it would be rather tricky to do.
Maybe some animation? Do a the action "climb" near a tree, to climb and sit on a specific place? Would be the closest to possible that I can come up with.
What I really would like to see though, is felines sharpening their claws on trees. And more actions. Stretching, yawning, roaring, howling, laughing etc :3