|Cult of Vorg|
Even the Star Wars movies, I believe they made it a point about having each jedi's fighting style and/or saber design unique, if they weren't supposed to just be a faceless mook Jedi. And now I've thought about SW movies, time to go scrub out my brain. I don't know that there's ever been an interesting Jedi.
I wouldn't enjoy seeing two machine-gun archers in the same group, unless the players where both OK with it. But, a one-shot sniper (maybe spell channeling or mythic vital striking) next to a standard rapid fire build would each give them their own thing. Or say multiple people like rapiers, I'd hope they could each find their own role, fencing grace kensai, sword n board brute, aid-another and butterfly-sting tricks, wielded in a tail for defense while casting or ranging, etc.
Unique combat styles, or approved/acknowledged competition, help to continue roleplay during combat.
It could be fun to have a game where everybody's part of a shortsword infantry unit, with identical combat training and style, and obviously unique personalities, but everybody would have to be OK with it, and if one or more of the group wasn't, we'd have to decide to either exclude them, bore them, or do another game.