No doubt Midland / Penetang area have some good marinas, but if you want to get away from the crowd, move north. I grew up at Sans Souci and still work there every day from ice out to freeze up so when I bought my C&C I decided I didn't want to spend my weekends at the "office". We are located in Britt and love it. There are not as many islands to tuck behind [as the south end of the bay] for sure but we never had an issue finding a private spot.
Extra time in the car though !