The hops are fine. Do 60 min boil, 1 oz Centennial at 60 min. 1 oz Hallertau 15 mins. If your going for a german style wheat I would increase the chocolate and crystal to 1/4 lb each that will get the color in the right range. This way you will get more complexity too. Definitely ditch the maltodextrin your all ready gonna be heavy on the ABV even without it. And go for the peach, its different but could work. Are you comfortable working with liquid yeast? If so try the Wyeast American wheat, it would work with the peach flavors a bit better.
Cheers!