I had posted some months back about what the OP is asking. I have not found good places for soloing at level 70-85. I've grinded a lot of Deep Ravenswood, Crag Foothills, and Grannus zone (though too many elites at the end of Grannus to solo). But with none of these areas is there really interesting content or questy stuff beyond just grinding on enemies. There are a few areas with mobs too tough to solo at level 70-85 that are designed for grouping (though I gave up on grouping because of the awful hitching I always experience in groups). It would be cool if there were more content things to do after obtaining the Shroud. Even story-based dailies would be a step up from simply grinding the same old monsters (and even then, in only a couple select zones).