Hognose are *technically* venomous but not dangerous and wonderful pets with a lot of personality. They're also a snake that you'll see out and about during the day. I hear Kenyan sand boas and rosy boas are also good options for the really small guys. I actually wouldn't suggest a California kingsnake for a beginner, at least not mine haha. She's generally pissy [literally pees on me when handling] and is the snake I trust the least, handle the least, and is the hardest to handle out of my three. Kingsnakes don't hang on like other species and they are constantly moving which can be fun when handling but also takes more attention and work, don't want to drop them! But I do love my Cali King, she's very inquisitive.
I am, however, absolutely partial to rainbow boas. Normally, I wouldn't necessarily suggest them a starter snake but you did say that you wanted a sunbeam snake and they are somewhat similar with all that rainbowy goodness. Rainbows aren't incredibly easy and aren't the most forgiving but once you get the set up right, they aren't hard. They take a little more time managing the set up for the right humidity but I don't even need to spray every day to keep the humidity where it needs to be. They have a reputation for being 'bitey' that's pretty undeserved. Rainbow boas don't seem to bite any more than most other species though newborn babies are nippy [like so many other species]. They also can't be in temperatures over 85 F so if you live somewhere where it gets pretty warm or don't have a/c, it may not be a good choice. Also, they get up to 7ft for females [usually 6ft] though they are very slender, but that may be over what you consider a small snake. They do great in tubs though!
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