Have anyone ever stopped and thought about how RO works? Seriously.
Paladins are hunky with massive amounts of HP and the ability of protecting allies, acolyte and mage types usually come with a low health pool and get either very useful supporting abilities or high offense. Thief-types get high flee rates, archer-types get high hit rates. Assumptio opposes Lex Aeterna, Full Chemical Protection opposes Full Stripping. The list goes on, think about it and you can see.
That means; RO is based on team play, one class can cover the other's flaws as they work together. And usually forming parties is the best/only way for a class to show its full usefulness.
You want to suggest another PvP room where solists can live their selfish fantasies, go ahead, i can agree to that. But i can't agree to impose such method as a must for all teamplayers also.
Being that my point of view; suggestion reproved.
Fun Fact; i never won ladder, ever ^^