You've got a great Holiday Strategy. Have a wonderful time!
I've only been to Death Valley out of the destinations you mention. It's been a few years, but I believe there was one overlook that was marked "NO RVs." If a location posts that, please consider it treacherous enough to avoid.
Other than that, I'd say go for it and have fun. Remember to turn a little later than you would in a car, AND that the rear swings out, opposite your turn. So, on a hard right in a two lane road, your back end may be in the oncoming lane
Soo many, Too many, gas stations are set up with the lanes facing the building and very hard for an RV to get through and out. Nothing wrong with deploying a spotter to make sure you're clearing everything. I'd rather look like a Noob than crunch something.