Travis, some ideas from my limited personal experience:
-The Minong Ridge is for sure a must do, especially the section from Washington Creek to Todd Harbor. The mix of ridge walking with occasional big views, boardwalks, forest sections, and beaver dam crossings make it super entertaining and aesthetic. Don't believe the hype about it being super hard or hard to follow. It's not a dirt sidewalk like some of the trails on the island, but that's a good thing!
-Todd Harbor is an awesome, awesome campsite. Very nice pebble beach, and a dock for swimming (if you brave the cold water!). I imagine Little Todd is even better, but haven't been there myself.
-Desor North did not come highly recommended, but I found it to be very nice. The sites are just a bit back from the lake in a nice open old-growth aspen forest, and while the lakeshore is bare rock there are spots to hang out and watch the sunset. The short spur trail to the Minong is a nice meandering, gentle descent through the same lovely forest.
-Daisy Farm is huge and has lots of people, but is quite a nice location. A great pebble beach. The Daisy Farm trail down from the ridge was also pretty neat, some cool boardwalks over big bogs.
-The coast trail from Daisy over to the Mt Franklin trail is good walking, some rocky bits but overall fast and easy. You get some good views of the lake and islands (and park headquarters), and there are some neat mine ruins right off trail.
-The Tobin Harbor trail is a speedy alternative to the last few miles to Rock Harbor. Flat and smooth through the forest, with fewer people. A bit buggy though.
In short, the idea to stay either on the coast or up on ridges seems to be a pretty good one. Though I'm sure it will be rough going, I really want to do some off trail hiking on my next trip there.