Hop flavor and aroma will mellow to some degree. It will not drop out. It will not taste as sharply bitter or smell as floral/grassy. For the majority of beers, 3-6 months aging I find greatly improves the overall flavor.
It won't kill your beer. It will make it greatly better.
I too have had a beer for 6 months in the primary. It had no off flavors. The beer had a very clean taste, even though the yeast had aalmost a peanut butter texture to it. There was no excuse for leaving it there so long, except for my Calculus class, wife and kids, etc...
Brewtaster- It would be easier to answer your post if you could say what style of wheat beer you are trying. Most yeasts will ferment a wheat. What matters in selection is the flavor profile you are tying for.
I find with all grain I am able to control the color of my beer better. With LME it always seemed darker. Even with full boils and late addition of the extract.