Did not know the OP wanted a quiet, beautiful state parkish type place..... thought he wanted something for MOA. Mystic Lake is close to MOA, a very nice RV park (not a paved lot), large ponds, trees, and far more amenities than you will use - including a huge RV wash that one can do a 40 foot moho in, huge swimming facility and even a full size hockey rink.
I lived about 20 miles from Mystic Lake for 25 years (Chanhassen) and watched the process grow from a white shack selling cigarettes to the largest casino between Atlantic City and Las Vegas. Hey, you can go over from the rv park to a wonderful buffet at the casino.