What kind of python fits this criteria?

[Tigergenesis]

I'm looking for a python species that could comfortably live in a 36x18x19 glass aquarium it's whole life. I would like a low humidity species. Without any extra work the humidity in the house & tank stay at about 30%. I would like a species that isn't too heavy bodied (lighter than a ball python) as I have some nice branches that I attached in the tank with aquarium sealant.

The tank currently houses my Ball Python, but I am planning on getting some Boaphiles and will transfer him over and need something to put in the tank. If there are no good species that fit my humidity requirements, I'd be willing to entertain a species that needs a higher humidity of about 55-60%. With some extra work (not much) I can get the humidity to consistently stay at this range.

Any ideas would be appreciated.