A group of small, active, diurnal lizards would make the best display. Anoles, Lygodactylus geckos, Curly-tails, or other active lizards will hunt, court, put on social displays, and generally entertain absolutely anyone who would stop to watch them. When kept in groups with one male and several females, there's virtually always something going on in there to watch.

If you keep them in an area with low but regular traffic, they learn to get used to the passage of people, and will eventually stop freaking out and hiding when someone walks up.

Ball pythons are great pets--but the small lizards are tops for an interesting display. None of the other species you mentioned can compare in terms of sheer enjoyment from watching them.

I just got a trio of Lygodactylus williamsi, and I can watch them for an hour at a time. They're intelligent, curious, and they're always up to something.

Don't let the low prices of some small herps influence you, either. Green anoles (for example) are great fun to keep, and that's what it's really all about with a display. A gorgeous fully-planted vivarium with naturalistic landscaping and brightly-colored, active, engaging little animals is going to make a much more dramatic impression than the lump of green stillness that is a chondro, or the occasional twitch from a bored frilled dragon basking under a heat lamp.

When you're setting up a display to WATCH (rather than just look at in passing), think of species that actually move around and do things that will hold your interest.