Can you give me reason why though, to make this interesting?
Connor is great fighter, I won't say he's on par w/ Shiva, but she was impress.
Roy is rough, but he fights pretty well, I might say he around Nightwing level or maybe above with tools at hand.
MIA - didn't care much for her.
The only person better than Dick in h2h here is Connor, and I think Tim and Damian are always going to beat Roy and Mia (as she's the weak link here), giving the bat-family time to gang up on the arrows. I do see the ranged thing being a problem at the start, but the bats are good enough to dodge those attacks imo.
Roy has a lot of history in comics, so I'm sure someone will back him up with feats, but I do recall him fighting Deathstroke and actually put a slight beating on him, until DS broke his ankles or something.
Roy's sparred with Nightwing a lot and done reasonably well, but Dick's become better since then. I'd think Roy could do pretty well against Tim in melee.
Tim's the best brain of the lot, teamwork and planning might be the difference.