from the before mentioned snakes i'd put in a recommendation for
rosy boas
rubber boas
spotted/childrens pythons
ball pythons
kenyan sand boas
i haven't managed to talk my mom into a boid yet so i have no personal experience w/ keeping these snakes except for reputation, occasional handling and second hand(i.e. know people w/ them)
if your looking for a nice big snake with an even temper then i'd suggest a golpher snake. sonoran subspecies are absolutly beautiful, imo, and can be very even tempered. i've had lots of hands on experience with these guys and if you get a really wild one they can be very aggressive but will usually calm down after a couple weeks/month hard work and lots of bandages, if you get a calm one they act just like kingsnakes except they musk when you spook them badly(not a plesant smell)