A Brazilian rainbow boa was my first snake and he was an excellent starter snake for me. Ate enthusiastically, was never nippy or snappy at all (unlike my current juvenile jungle carpet python, though she is getting a bit more mellow), no problems shedding, and loved hanging out on my hand while I read a book. As long as I kept him in a Rubbermaid box with a moist hide box, he was good to go. I think if you understand the upkeep of herps, like your lizards, you maybe could branch out a bit beyond getting just a corn or ball. I love both species, but others you could think about are:

-rosy boas. Make sure to get a captive, though that goes for any species! They are getting quite rare in their native areas because of the pet trade
-sand boas, though they keep pretty short and have neat coloring, they definitely look very "wormy"
-rainbow boas, if you find a nice amiable hatchling/juvenile
-milk snakes and king snakes, though they aren't usually too awful bitey, can be flighty if they aren't used to being handled

This is not an all encompassing list, but just something to think about. Looking for a responsible breeder is a great choice so that they can help you if you have questions or concerns.

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0.1 jungle/coastal carpet python: Sheila
1.0 anerythristic boa constrictor imperator: Severus Snake
1.1 rats: Eowyn, Gandalf
1.0 ferret: Walker Texas Ranger
0.0.1 gold fish: Tiger
3.0 dogs: Strider (Aussie/husky), Zoso (Belgian Malinois), Buck (husky/Rottweiler)