I'd recommend leopard geckos because your list of pets includes them and does not include a ball python. Otherwise, there is little to chose between the two species for your purposes, I think. There was precious little captive breeding of either lizards or snakes before 1970. I think that Sean McKeown popularized leopard geckos in the 1970s, while ball python breeding took off in the late 1980s or so. Ron Tremper is another important figure in leopard geckos.

Good luck.

Paul Hollander