I'd be strongly opposed to this. I've said for a while, 50-60 range (as used in your example) should remain mostly untouched, as balance isn't much of a concern there. I think tinkering with it could easily do more harm than good to the currently most balanced range in the game.
This would also ruin any sort of diversity there is at any level. 90% of bears at that range use either mace set or plat talon anyways, most mages use int sets, and almost all birds use dex sets right now, so I fail to see how this would do any sort of class balancing. I haven't been too active in 66-71 but from what I have this wouldn't really balance much either, and anywhere below 50 it wouldn't apply to anyways since no one uses sets there. All it would do is limit people and kill any level of diversity that still remains.
The only area this idea would help balance would be at endgame, which Cinco has already addressed with making the 2h weapons class specific. Applying this to levels below that would just be an all around bad idea.
Honestly, the more I read this idea and think about it, it's really quite nonsensical.
Bookmarks