I don't see it as usable. The Mozart connection is cool and all, but for English speaking people, it's the words "wolf" and "gang" put together. A wolf gang. Great. And what could you call him for short? Wolfie?
My daughter actually considered this for a brief time, because she's a great admirer of Mozart. In general I stayed out of her and her husband's name considerations, knowing the choice wasn't mine to make, but in the case of Wolfgang I felt that I had to step in and strongly advise against it.
Eddie Van Halen and Valerie Bertinelli got away with it because they're celebrities, so their son, as the child of celebrities, would probably be immune to the ridicule an ordinary child would be subject to. And aren't celebrities supposed to be quirky and different? But for the average child, yes, it's too much.