We've never gone to to Pelee Island. From what I've read about it there's not much there to see. A few years ago we did pan to take the ferry there but there were high winds and the ferry was canceled, we never attempted again. The closest we got was Point Pelee Park. At the park I was amazed at the turbulence of the water at the tip of the park.
That area of Ontario is one of my favorite places, especially Amherstburg. Prince Edward County is another favorite.