I wouldn't put L. williamsi in that large of a setup. They'd get lost. And $25 for a giant day gecko is a steal!!! The anoles would be fun to watch displaying though, especially if there were a lot of them. Or if you can find them, Cuban knight anoles (although more expensive) would be larger and more visible. It all depends on the effect you want to go for.
ANd if you want to get a really interesting plant that will eventually reach the ceiling, get a Nepenthes pitcher plant or two. They've been known to take over trees and have some very interesting leaves.
It would be kinda fun to put a pigeon in there on occasion and see what happens. I'm only joking, that would be risky.