Thank you, guys, for all great tips. It is our first trip to Colorado, so I am not sure what to expect.
We arrive to Denver at 8am. Google shows 1H30min to Colorado Spring, so I assume by 11:30 we should be in Co Springs, at 1pm at the Peaks, spend there 3-4 hours and spend evening on Col Springs. Is the air at the top thicknesswise much different from the Grand Canyon?

So if suggestion is to spend more time around Durango, Ouray, Silverton, should we cut shrort our days between Moab and Denver on the way back do in in two days instead of four. For example do night in Vail, night in Boulder and last night in Denver?