My only complaint(s) is the leveling path and rate. I don't mind slow going. The longer the leveling process lasts for me, the better. Once I hit cap, the majority of the world is just an obstacle between me and loot. What I do take issue with is the clarity of the leveling path. With limited planarite, I can only participate in Hunt Rifts I come across (opened one of them myself), and between those, regular rifts, and the various forms of quests, I'm still quickly outleveling zones.
At 52 I'd already completed Cape Jule, City Core, and parts of Pelladane. When I jumped (literally) from City Core to Eastern Holdings, I was in a new world that seemed above the expectations for someone my level. Having to kill progression and go back to quest in past zones is a bit of a buzzkill.
Oh, while I'm here, I'll ask: For anyone who completed City Core and moved on to E.H., did anyone else having a hard time finding the bunker after that Prince comes and saves you from the cannibals? He's like "Follow me to the bunker!" and then just despawns. Took some effort to find out where the hell I was meant to go.