Thinking about growing hops next year and haven't brewed for very long, so i'm not sure what variety of hops would be most versatile for the most types of beers? What do people keep in stock at all times?
Cascade and Centennial are great growers for the northern parts of the US.
I generally keep Magnum for bittering, and Cascade and Centennial in stock all the time. If something comes up on sale ( usually I buy thru Nikobrew.com ), I'll pick up a pound of that to try different recipes. ( I got a pound of Citra last year for less the $20 ).
Mikkeler has a series of IPAs brewed with single hops that might help clarify your choices, if you don't already have some favorite hops. I don't like grapefruit very much, in or out of beer, and accordingly am not a fan of Cascades.
+1 on picking your favorite beers and seeing what they use. For the wheat beers you listed, Mount Hoods might be a good choice. They are derived from noble German hops and are more robust growers than the true noble varieties.
If you're growing hops, whatever grows most prolifically where you live is the most important factor, everything else is secondary. I grow 8 kinds of hops but Willamette and Chinook yield the most hops for me where I live.
Agree with GVH Dan, grow what you use. This year I grew between 1 and 3 oz of numerous hops and 22 oz of Chinook. If I DIDN'T use Chinook, those hops would have no value to me. So again, grow what you use.