I think it's just way too much. I would think that the night is for the candidate himself.
I was initiated with 2 other brothers, passed and raised with 1 of the 2. We become very good friend and we called ourselves Masonic Twins haha
However when I did my other degrees, Mark, Holy Royal Arch, SRIA, Shriner, I was the only one candidate. I feel special on that night. I think it would somehow spoiled the experience if you are the second candidate, especially maul in third degree and axe in Mark degree.
Under UGLE, the maximum of candidate in a ceremony is limited to 2 only, furthermore you'll need a dispensation from the GM, MetGM, ProvGM or DistGM for that. But as I'm in an universities scheme lodge, we do multiple ceremonies, the ProvGM granted a dispensation for those dispensations only on my lodge and one other university lodge in the Province.