Mackinaw Creek now has big rig sites with 50amp service. Not on the shore but close enough to walk to the water. Nice views of the Mackinac Bridge.
For an upscale experience try Bay Harbor RV Resort in Charlevoix. If you book now, the rate is only $49/night....beautiful resort...
If you have kids with you, be sure to visit the shoreline for Petoskey Stones...they will keep the kids busy for hours...
BTW...on the Island, WTF means "Where's the Fudge"...:W......Dennis