Joe, I haven't been to Redwoods NP yet, but have hiked Muir Woods north of San Francisco about 15 years ago. Incredible!
Bee, not sure when you visited DV, but winter is the time to go. Not only are the temps comfortable-to-cool, but the air is mostly clear of that summer heat haze that turns everything grey. The color of the rock can be just astounding - striations and patterns everywhere. A spin around Artist's Drive is just as colorful as anything I've seen in southern Utah or Badlands NP in South Dakota.
