I've been to Cape Croker, which is at the south end of the Bruce Peninsula. Basically you're on the tip of the Niagara escarpment, so there's lots to see there - birds, cliffs, Georgian Bay... There's a remnant black bear population on the peninsula, but standard precautions are fine. You'd have to be VERY lucky to see a Massassauga rattlesnake - they're endangered and protected. There's a fair bit of poison ivy in the area, though so watch for that. And if you can get away from Tobermory on a clear night you'll find you're far enough from any major city to have an amazing sky.
Mike.