Scuffles are often inevitable with pairs, and there'll always be a dominant one. You can't stop it, they're like that. The general rule is that once blood is drawn, separation is required, but tbh i don't like to leave it that late.. you get the message when one/both of them is unhappy.
I'd keep them together as scuffles happen more often when they're young, once they've reached 'adulthood' they seem to settle down
That said, some pairs don't work out at all.. so it's really based on your 2