It's still "monsoon season" so you may get some good cloud action.
From what I saw try to get the guide to take you as far from the visitor's center as possible. The number of cars and people was really surprising to me. I believe the further you go the more the traffic thins out as the truckload tours are short so can't go too far.
Good luck, it's an amazing place.
VOG is really easy to get around. If entering from the north there is a wash about 200 yards from the paved road, it you can traverse (no water) that you're good to go for the rest of the loop. There are a couple of "whoop de do's" and blind corners but nothing needing 4wd as long as the road is dry. If you enter by the B&B you cross the toughest part of the road first and the rest is pretty smooth. The dirt road is about 18 miles total and stopping for photos took me 3-4 hours each time through. Beautiful and peaceful, there are very few cars and you can hike for an hour without seeing anyone.