On the how often do I get bitten front, well, that depends on the day, the seek, and what I have to do. If you are going to keep a number of different species of reptiles, you are going to get bitten by something. You have to be able to judge the individual animal. The last thing that bit me was my male leopard gecko, 'cuz I leave him in with his two girls, and, well, I think he was a bit randy I prefer my hands. It's easier and faster, and less stressful to the animal. And the snake is going to get used to it at some point, so why not now? I do have a small and larger hook. But I only use them in certain situations, if I know the snake is going to have a go at me. If for whatever reason there is food involved and I have to move something, which doesn't happen often. If there is the smell of rodent, anything warm will get tagged by some animals.
A snake is not naturally more aggressive just because it is venomous. Tom interacts with his animals regularly, and those were captive bred, so they are very used to humans. The only "general rule" I have come up with, is arboreal species tend to be more aggressive. Which brings us to how to get a snake off of a branch? If it is a captive bred animal that is used to people, and me in particular, I unwrap it and take it off. With young green tree pythons, and to a lesser extent emerald tree boas, their spines are fairly fragile at a young age, so I "tickle" their tails to get them to crawl off the branch on to me. The snakes that can be a pain to remove are my carpet pythons. They are very unusual animals, they have prehensile tails, like all snakes in the morelia genus, (including green tree pythons.) So they can really wrap around and grip, anything. They are like a cross between a Burmese python and a green tree python. They are smaller, and not quite as strong as the giants, but most are larger than, and much more strong, than a green tree. So if one of those is perched, and doesn't want to move, it can be a bit of wrestling match. I can't fins a good pic of one wrapped up at the moment.