What other herps do you have?
You mention you want something less common for an intermediate keeper, but I am just wondering if your experiences would be as relevent to lizard care? I don't know a tonne about lizards, but I do know that they can vary quite a bit, as with other herps. I mean I'm sure there are transferable skills there as well, but you can never be too careful! I totally understand the uniqueness factor, but there might be other species to check out as "starter" lizards, to get you eased into their care.
Just an idea.

Best of luck!