I voted for the northern end of Baxter, but here's what would really be great - how about the Moosehead Lake region? You'll see stuff you never saw before. Big and Little Moose, Big and Little Spencer, Kinneo, plus the Elephant B52 wreck, plus bushwhacks you'd never imagine (and which you may want to soon forget). And with a drive over to Jackman, Boundary Bald, Coburn, Mosquito, and more, much more.
Get beyond the plain old HH, and go off to the woods!