I've hunted Drummond Island quite a bit, though not for several years. The Potagannising River and the chain of lakes on it (1-4) can be very good hunting. I'd recommend a small rig with a mud motor if you plan to go very far upstream, as the lakes are shallow and weed choked and the river usually has a few beavers doing their best to slow the flow, so you might have to get out and pull over a dam or two. Because of this you'll have less competition the further upstream you go, but there is private property access directly to the river on the upstream sections, so there's always the chance that you'll run into other hunters even if there are no other vehicles at the launch. I suggest that you scout it well during the daytime, and mark your paths with a GPS, so that you're not frustrated when you head out in the pre-dawn. We've taken lots of puddle ducks off of those lakes, and if there's a good blow going on out on the big water, it can bring in a fair amount of divers seeking shelter, too. I have seen the sky above those lakes full of ducks one day, only to have them ALL pack up and head out on a weather front leaving none behind the next morning. But that's hunting. Openers are always crowded, like anywhere in our state, so I'd avoid hunting there for the opener unless you enjoy that kind of thing.... One year we headed out to our campsite on a small piece of high ground out in the marsh on the Wednesday evening before the opener, and by mid-day Thursday we'd already turned around several other parties who had hoped to camp there! That was 2004, and we haven't been back for an opener since! Later in the season, you may find yourself all alone out there, and a good hunt on a day like that is really satisfying.
The Potagannising Bay on the NW side of the Island gets layout hunted quite a bit, but I've never hunted out there myself. I have fished it and you need to go slow and carefully as there are a LOT of rocks right below the surface just waiting for your prop! This is true of much of the offshore waters around the island. Finally, if you are hunting the big water and the weather begins to turn: HEAD IN! It can get really nasty, really FAST. Have fun up there, there's some good hunting to be had. But be safe!