tbh if I can think of a set that requires very little aid from cube powers or wearing other leg powers, i'd say GoD DH is the easiest to do a gr70 solo with just about the set it's self. granted i haven't played all the sets or anything, but this one gets strong very very easily.

Crusader full valor does about the same gr65 easy with set. I have full legs too for gr100. Legs and extra set boost 30 to 40 gr.

1-70 should be done after 2 hours,than again 1 hour + to get the 6er set

than pl service

Doing the seasonal journey will give you set pieces.