We have done the Debsconeag loop a few times putting in at Ambajejus Lake at the dam, traveling west up Pemadumcook, carrying into 3rd Debs, 2nd and 1st, and then running down the West Branch back into Ambajejus Lake to finish up. We even did that trip in reverse once going up the Penobscot, but I don't recommend that . All these trips were done in W&C.
We were wind and storm bound once on White Horse Island in Pemadumcook near the outlet of Lower Jo Mary Lake. You can easily carry from Lower Jo Mary into Pemadumcook (you might need to clear some brush). There is a shoot there too that might be run-able, but the water was a bit too high the day we were there for comfort.
That sounds fantastic! Which portage is the longest?