If you can do overhead heating and lighting Rankin's dragons are neat, one would happily live in that space and captive bred ones tend to be very tame once they're familiar.

Garters are lovely display snakes and my captive bred female is actually remarkably tame, accepting tong feeding and not musking when I have to handle her for moving and cleaning, but if you try to handle them too long they almost certainly will musk and they're quite timid and flighty. They learn pretty quickly that stuff outside the viv isn't a concern but if you want handling like a boa they're not a good idea. You can probably keep 2-3, though, garters sometimes cannibalise smaller snakes but they are gregarious in the wild and they may be less stressed around other garters, especially while growing up.

There are some amphibians that'd work well too, African bullfrogs, pacman frogs, and tomato frogs grow impressively large and are usually cool with hand feeding and fun to watch. Their skin is too delicate to regularly handle without gloves but tiger/mole salamanders make great interactive pets for the half the year they're not hibernating.