Welcome to the RTA Forum!

Your trip certainly look achievable, with note that many of the drive times are a bit low, however, there are two spots that stand out.

You don't actually list any day going from Monument Valley to Grand Canyon, and the two are really too far apart for it to be considered the "surrounding area." It takes a few hours to drive between the two.

I also would not recommend at all trying to do Disneyland on the same day you drive from Vegas. Disney really is a full day activity where you don't want to try to start it after being on the road for 5 hours.