The Valley of Fire hike was our absolute FAVORITE part of our trip to Vegas! The area itself is GEORGEOUS, but what took the experience to a whole new level was our Love Hikes guide, Adam. He has a wealth of knowledge about the area, is passionate about his hiking, has a WONDERFUL sense of humor, and was SO encouraging when my wife was initially concerned about exposed heights (he started off by choosing routes that avoided higher places but kept offering her opportunities to define her own limits...by the end of our hike she was scampering around on paths that I never would have guessed she would be comfortable on!)
And did I mention that the Valley of Fire is GEORGOUS?!?!! If you don't mind getting up a little early, I really recommend doing the sunrise option. I'm not sure how busy it might get later in the day, but it was SO peaceful and quiet at that time....just saying!