Alex - I've been to both: Shenandoah when I was very young and Smokies when I was in my 20s. I still prefer Shenandoah likely because it made a better impression on my young mind. As for the Parkway I think this is the best stretch for foliage views (mm. 450 to mm. 300). There are a lot more scenic sights here, though I haven't sampled Virginia's side yet