Both of mine are fixed.
I think that, generally, it’s the unfixed females who are most aggressive and territorial. Males can spray (usually when there are other rabbits around to mark territory against) and hump, but I haven’t personally known or heard of any unfixed males who were particularly aggressive. I have heard of and known some females who were though. Some were still territorial and aggressive after being spayed, because those habits were ingrained after so long. If you won’t be able to get the bun fixed for a while, I would absolutely recommend a male over a female.
I didn’t know Hannah before she was fixed, but I had Otto for 3 or 4 months before he was neutered – his litter habits were perfect and he was never ever aggressive (his man bits were there from 8 weeks, so he must’ve gone through puberty during that time). Despite his great personality I wanted to get him neutered as soon as the vet said it was ok. I just think neutered animals are much happier and less stressed animals.