Utah - planning advice

Cdash wrote:
We are looking to do Utah this summer. We are National Park type of family, stay in the park sites with no hookups (35' fifth wheel), do some hiking, Ranger programs, and enjoy nature.

We are thinking about visiting at least Arches, Canyonland, Bryce and Zion. We'll have 16 days total. We'll likely push hard on the way there and back to make the trip in 2 days. That will give us 12 days in the parks. We are crossing places of the bucket list before the kids are done with school, so we do the best we can with the time we have.

How many days would you spend in each park? I know we'll never see it all, but will make the most out of what we have. Any suggestions are appreciated.

Anything not on the list that absolutely should be? If so, what and why?

Lastly, will July be too hot to enjoy anything? Should we wait until 2018 to try to do it in mid June?

We did almost that same trip. We spent several days @ Zion and just one day at all the others plus three days in Moab. The scenery at every one of them is something to behold. It was almost overload for us. Yes I believe June is already too warm for my taste. We were there in mid April 2016 and were already quite warm.