If you are coming from MI through OH/PA, you can take 90 up to Niagara Falls if you want then I-90 to the finger lakes. Kind of touristy and overpriced IMO, but worth a day maybe. Or take I-86 across southern NY. Either way, check out Letchworth SP as a possible stop on the western side of the finger lakes. Then as you go east, lots of choices, but I would recommend Seneca Lake. Wineries, race track, lots of farm markets, boat tours... Watkins Glenn on the south end of the lake is great. There is a nice KOA ($$) or we really like the state park. Only one loop with electric at the SP, so reserve early. From the campground you can access the top of the gorge trail and walk down into town. Or, if you like to bike, consider Sampson SP. Its up the east side of the lake. Its a former Navy training station. They leveled almost all of the buildings on the 2000 acre property, but left the paved roads as bike trails.
From there, its I-90 east to the ADK's. Several possible routes through the ADK's and all of them are nice. My recomendation is get off in Utica and take 12/28 north to Old Forge. Old Forge Camping Resort is great, or there are many SP's (all without hookups). Eighth Lake, Nick's Lake, Limekiln Lake, or my favorite in that area is Golden Beach. Lots to do in that area. Check out the canoe/kayak rentals on the Moose river. There are some easy half day paddles or more if you want... Boat tour and the ADK Scenic Railroad are both good too. From there, north through Inlet, Racquette Lake, Blue Mountain Lake - all interesting little spots to check out. Then Tupper Lake, Saranac Lake, into Lake Placid. Lake Placid KOA is one of our favorite spots. Tons of hiking and fishing spots.
Alternate route would be Utica north on Route 8 to Speculator. Either Moffit Beach or Lewey Lake SP would be good spots. Then north to Blue Mountain Lake and on to Lake Placid.
Not sure how you plan to return, but if you stopped in the southern ADK (like Old Forge) then went to Lake Placid, a good choice would be head west across Route 3. This would give you a chance to hit the Thousand Islands region. We really like Cedar Point SP. Can get full hookups and they have sites right on the seaway. Great fishing, and Alexandria Bay is a little tourist town close by. Then either 401/402 home through Canada, or I-81 south to I-90 west to PA.
So, short story - check out Watkins Glen/Seneca Lake, Old Forge, Lake Placid areas as base camps and go from there.