I'm almost sure this has been said somewhere, but I'd like to see a reason to level up Dexterity in that it can be beneficial to some characters. That idea, is Critical Hits. Perhaps Dexterity can also be tied in with your combat skills to give a % chance of a critical hit, like say at Dexterity 100 with Axes 100, it can be a 10% chance of a Critical Hit to keep it balanced (at least for PvP). So another example would be Dexterity 100 and Axes 50 would be a 5% chance, and Dex 50 Axe 50 would be 2.5% chance, hopefully this makes sense.

Maybe another use for it could be the speed at which we travel on slopes, as we would need pretty strong legs to move up slopes effectively. Eh, this second one was a pretty weak idea, and I didn't have much to back it up with.

Tell me what you all think! :D