Wow.... you are right there is so much that is so close.
We have booked our hire car and collect the car on the morning of the 10th at our hotel and need to drop at Las Vegas Airport very early on the morning of the 17th so our 7 days may actually end up being 6 as the last night will most likely be spent in Las Vegas. At this stage that is all that has been finalised.
I looked up Antelope Canyon and love what I see, the rock formations are amazing and will definately have to be included in our road trip. Everything I have read about Antelope Canyon says you need to be on a tour to see the formations. Do you know if this is something that can be easily done when we get there or would we need to book in advance?
We are looking at having a rough plan of where we are going and not booking much in that week so we have the flexibility if we see something we like to stay a bit longer. The only reason I choose Denver as a destination was the forum that I read about the I70 and the pictures that were attached looked great.