I'm more worried about the ARA types honestly. I keep a good standard of clean/ventilation/temps and I live in the middle of nowhere so I don't think AC is going to have an issue with me. We have cameras on the property now after we had someone poking around who broke the windows on the barn...
I'm just getting into rex as well. The breeder I spoke to supplemented with flaxseed and black sunflower seeds. All of her rabbits looked really good and she was winning at the show table with it. I'll probably do the same for mine because of how hers looked.
A good squeak should do it for the boys and they need to get on top of that biting behavior ASAP.
I used to have a lop doe from hell. Put her on the ground and she'd growl and aggressively nail your ankle with her teeth. Next to her cage? Lots of growling and lots of thumping. Offer her a...