Thanks! Glad you like!
The northwest side of the park is the best in my opinion, you'll find the majority of the rock structures there. Cap Rock, Jumbo Rock, Intersetcion Rock, and Skull Rock provide a lot of shooting opportunities right from the car. The ride to Keys View will be worth it also, being at a higher elevation you should be able to cool off a bit too. Sunset might be best from anywhere around Cap Rock and Intersection Rock.
Be careful around Jumbo Rock if you go. There are bees everywhere!
I'd take your time in getting there, the light won't be that great until after maybe 3-4. Swing by a grocery/convenience store and get more water than you think you'll drink, some sports drinks, lunch/snacks. You burn up food/water at a suprising rate out there. It was 100 degrees at 11:00 am last Sunday, from 65 degrees at sunrise. Don't underestimate the desert! Go for the SPF 50 sunscreen too!
Let me know if I can give you any more tips, I'd be glad to.