I think he's looking for a solo area. He could have gotten most of his gear and exp from raiding/grouping and just now is looking into area where he can solo before.
I've done pretty well with AA exp, even at level 70, in Droga. I just kill everything around the king area as quickly as I can then move further out if I need too. Plus you might get some nifty drops for selling/tribute, like Sword of the Bloodsworn and Copper Hammer of Striking. This is an easy, laid back zone at level 70 with semi-decent AA exp.
Ruined City of Dranik might also be a good spot to check as alot of it is kitable and tons of decent attuneables drop here for twinking/selling/giving away.
You could probably solo some of the noninstanced DoN zones, like Ascent, but I've never spent enough in these to know what the exp would be like. I have found many of the drops to be kinda lackluster in these. Though there is a nice Healing Improvement V aug in Stillmoon, it is no-drop.
Plane of Hate doesn't have super great exp, but it's fun to tear through from time to time hoping for a Shield of the Immaculate to drop. I think everything in this zone is still dark blue at level 70.
Tons more spots around. I would just wander and see what you can find.