I would definitely suggest carpet pythons (i have one baby IJ for sale, btw
). They are active, tame (even as babies, usually!) great feeders, attractive, small size, etc etc etc.
As for humidity, if you build the proper type of cage you won't need to do much spraying. All of mines are in wood/glass cages with half their water dish over the heat pad. I spray them all about once a week - and you should definitely NOT be forgetting to spray your snakes, thats not cool. Even a colombian boa needs to be sprayed.
Anyway, I live in Toronto too, and you're more than welcome to come see my set ups and snakes and stuff!