I always think rabbits are so like us - they yearn for company but are very particular who they live with. The territorial nature and a natural pecking order means that we have to bond them before they can live together. This is should be done on neutral ground where no rabbit has any sense of ownership.
We have a very happily bonded pair, Polar and Bear, but it did take a good two-three months of them living side by side and meeting at a mesh chatting wall to achieve this. Bear was very happy with his first partner, Mouse, who died of old age. He was lying next to her faithfully after she had passed away. So we didn't rush him but clearly he needed company. Polar was rescued to live next door and be just that.
Polar was younger but the partnership worked well and even after Bear's illness she continues to care for him. They have plenty of opportunity to be apart but we usually find them together side by side contemplating.
We did have a larger group (7) but when they were established themselves with us there were two females who just couldn't get along. I had to be on watch to see how serious the scuffles were and the group was split to a 4 and a 3. This resolved the issue although I was sorry they had to be split.
A bullied rabbit in the wild would clear off, maybe join another group or just keep its distance. The dominant rabbit chooses where he or she wishes to be and collisions with a lower rabbit can be tense and sometimes you may have to remove the unlucky one as it is unfair to be trapped with someone who doesn't like you.
In this situation I would try to bond the ousted bunny with another and let them interact safely with any other rabbit groups. It is always entertaining to chat with the neighbours! If a rabbit becomes very grumpy and you feel he can't bond, he could at least be near and able to chat to other rabbits safely. I have never had a rabbit I had to isolate completely luckily.
In the runaround we try to give two exits wherever possible and quick escapes are handy for a rabbit who has to keep avoiding a more dominant one. If there are two resting places they may settle for one each and tolerate each other better that way. This is the case with Mrs Nice and Teddy. They can be together but favour their own space too. They come from our group of 4 and Maestro and Barry were probably higher up the pecking order. Eventually it was just the two of them and Teddy definitely prefers some time by himself but they also can spend days side by side.
In the early days I used to pop into the run and sit quietly while they had their evening treats. You felt you were at a social gathering. Their behaviours and antics are so cheeky and clever I felt I could be part of the gang for a moment. They were not paying attention to me but by just lying low listening to them munch and interact I felt part of their group and it was a very happy feeling.