Figure on a quick drive past Monument Valley on the highway, and maybe consider a drive (for free) through Valley of the Gods instead. All in all it's worth about 3 hours IMO.
About Sequoia, I haven't been there yet but there are a couple of groves of giant redwoods in Yosemite. So you could skip the former and see the trees in the latter.
After seeing Arches and Bryce Canyon, the smoother rock faces of Zion seemed bland to me. But the people coming back from hiking the Narrows were all saying it was an experience of a lifetime, so I want to do that someday. And it would be cool in the Narrows even when otherwise hot at Zion. I didn't do it (was only there for part of a day), and I really regret that.
Bryce is at higher elevation so it will be a bit cooler. It's a good place to spend a bit more time.
Capitol Reef is best seen by driving around IMO. You might like that, although to me Capitol Reef did not stand out especially from all the other spectacular Utah sandstone scenery. Whereas Bryce and Arches stood out because of the unusual wind-sculpted shapes. And especially Arches, for the sheer close proximity... you can stand right inside or next to many of those arches.
I would add a drive through Colorado National Monument (figure one day so you can stop at every lookout), with a night spent either inside that park or at the state park to the north (just off I-70). It's right along your route home anyhow. This place felt like my private sandstone playground... somehow more intimate and certainly far less crowded than most of the other places.