There's still ways to power level as you can have someone help kill the capstone boss then stay teamed with them in WT3 for 200% xp bonus. Someone already managed to be level 3 in WT3, which was minimum possible from gaining XP from the capstone dungeon quest.Yup, it also removes power leveling as well. Everyone fights mobs at their own level, allowing players high level and low level to party up and have an fun experience.
I really like the group scaling system though, it works fantastically.