Good thing you revived this thread of yours.
Beginner snakes, imo, are Kings and Milks ( for those who like feisty ones and cna handle that awfull musk discharge).
Corn snakes, without the feistiness and the musk.
And Ball pythons, for those, like me, who don't care for Colubrids ( except some non mentionable in this thread ).
All the others mentioned require a little more experience, or, at the very least, age and maturity from the first time owner, imo.
Bloods ( Brongersmai ) used to be agressive. All of them. That is why they were called Blodd Pythons.
And the same goes for both the other two species of Short Tail Pythons ( Breitenstieni, aka Borneo and Curtus ).
They mellowed a lot, with captive breeding programs and are now perfectly manageable snakes ( with some exceptions, of course, because some are mean as hell ).
Anyway, Short Tails can be a beginner snake, if the person is mature enough to handle such snake. They get as thick as a man's calf and some females can get to 7 feet. They are heavy and very strong. And if, joined to taht, you chance on a nasty one, it is not fun.
As to poo retention, I have had a female retaining poo and only being able to get rid of it with a long swim in the bathtub.
As to RH, in my experience ( and on others experience also, as already documented in MFK ) the young ones are very prone to respiratory infections and they do die from that.
People keep them too humid, imho.
My 2 cents, for starters