Let's see how it turns out to be in the end, a lot depends on what others will do, as well. We'd love to have more competition and more variety of clans at our level.
You won't (or shouldn't... rather) be able to fight someone unless you're on the same combat system. I feel like I could kill 10 Legacy users so long as I have access to abilities. It would be unfair.
Yeah... there's just no way to counter stuns, bleeds, and prayer drops without abilities to break or reduce damage. If they seriously let it be abilities vs. legacy in wild it would be deader than dead lol.