What a coincidence.... I just happen to be drafting a dark strong recipe as we speak. My research on "the best" recipes (in my opinion) has led to the following conclusions so far as to recommended grist:
Pilsner base
CaraMunich
Special B
Dark Candy Syrup
Those are all required. Also optional:
Aromatic
Munich
Other malts aren't used as much.
As for hops, many people use Styrian Goldings or Hallertau or its derivatives (Hersbrucker, Mt. Hood).
Many people are using WLP530 or Wyeast 1762, those are the big ones from what I can tell.
There's really nothing wrong with your original recipe at all, looks great to me. I would drink lots of it. But, as others suggested, it wouldn't hurt to simplify it a bit, if you want. I'd start by ditching the chocolate wheat, and trade the Crystal 60 for CaraMunich, that might be more interesting and a little simpler. Also maybe decide whether you want Vienna or Munich, probably no need to use both. And if you can get the dark candy syrup, use that instead of brown sugar. That about covers it. If you want. Your recipe would still turn out awesome. But just could be simplified, slightly, if you want.