Green Tree Python, Amazon Tree Boa, Green Bush Ratsnake (Elaphe prasina) Western Hognose, Garter snakes, most all of the species, and Rosy boas.
The first 3 are the most visible but also more difficult, in terms of husbandry and handling. The last 3 are ranked in order of visibility and they are all much easier in husbandry and handling, generally.
Though I'd say that the Hognose, Green Bush rats and the Garters are the most active, as in actually moving around during the day, the others just tend to rest in the open.