Firstly, I would like to thank you for adopting this adorable little guy. 🙂 My money is on him being a he, for I don’t see fur around his neck, which females often have, for when a rabbit gets pregnant, she uses the fur there for her nest. It is highly recommended though to get a bun spayed/neutered, for they get aggressive when they reach puberty and are not that fun to be around. They can also have a high risk of uterine or testicular cancer.
Rabbits are very nice companions, so I am sure you and he will form a bond with each other in no time. You sound like a very good-hearted person, which a lot of bunnies are attracted to. 🙂 He doesn’t seem like the timid type, hopping all over the place already, and those buns tend to have quicker bonds with their ‘hoomin’ friends. 😉
I’m sorry I do not have information on your other questions, I just wanted to drop by and share what I know, and to say thank you for rescuing him. 🙂 Other members have more experience with those areas, I’m sure you’ll have a healthy and happy bun in no time. Please keep us posted! 🙂