IMO, if you're looking for a great all around rider, then get a YFZ450, or really any of the 450's from Honda, Yamaha, Kawasaki, KTM, ect. The 450's are always great all around riders, whether it be trails, track or dunes.
If it were me though, I'd buy a banshee. There is NO feeling like a 2 stroke ripping wide open in the mornings