5. Go on "photo runs"
This is where I'd really pile the miles on the Jetta.
I like photography, and I would buy some seriously good camera equipment. As for what I'd do with that equipment, I would travel all across America taking photos everywhere I could in the most scenic areas.
An example of this is the Blue Ridge Parkway. I've never been there and one day want to go. When I do, I want some seriously good camera gear along for the ride.
Another thing I'd like to do is a Route 66 run. Lots of stuff to see, and I'd take full advantage of it.
Every state in America has something worth seeing, and I would like to try to photograph it all. It would take years to do, but I'd obviously have the time.