New Enclosure - What species would be good?

[ttreptile1]

I just spent the last month rehabbing this cage I happened across on Craigslist. It was a steal but a lot of work to get it like new again. My question is what species would thrive in an enclosure like this? My first thought was Green Tree python which I have experience with. My son wants a lizard of some sort. I am just leary of adding anything clawed into a acrylic cage. It's 6 foot tall with stand (little over 4' cage wise) 30" wide and deep. Has a fan ventilation system built in. Will be adding heat and misting system shortly.

Thoughts? Suggestions of species or needed modifications?