I've got to say, this would solve so many grind/boredom issues.

Every melee class grinds alone from 1-30.
To other players (mages or casuals), this is infuriating.
To the grinders, this is skull-numbingly boring... but you have to do it, otherwise you'll get chewed up by some bastard who took the time to perfect their own skills.

Net result: lots of boredom for everyone. I have made a few come-back characters and not one of them got out of 30's ... because by the time I was done grinding, I was bored. The only exception is my one and only currently active character, who did not grind (and is now regretting it, because post-40 range seems to be full of foes who mastered their skills).

Net result: I feel that this change would benefit everyone.
Grouping would be fun again -- imagine being excited again to seek to group with someone? Since I don't play mages, I didn't have that feeling in years. There would be less mindless boredom for everyone involved. And I'm willing to bet Galadon pies to gold coins that the player happiness would shoot upwards.

I know I'd be playing more, for one.