Wow, thank you for reaffirming my initial thoughts!
This is an August 2018 trip for my wife and I, plus four kids (11, 9, 7, 5). I need to start making reservations and want to nail down my route. Here is the trip so far...we have about 32 days total to use...so I have about 3-4 days to add to the trip still (ie. maybe a day in St. Louis on the way out).
We have a 40' 5'r so likely will not be able to stay in all the parks.
Day 1-4 – Drive to Grand Canyon (35-hrs)
Day 5-6 – Grand Canyon NP South Rim (2 full days)
Day 7 – Drive to Lake Powell (3-hrs)
Day 8-9 – Lake Powell (2 full days)
Day 10 – Drive to Zion (3-hrs)
Day 11-13 – Zion NP (3 full days)
Day 14 – Drive to Bryce (3-hrs)
Day 15-16 – Bryce Canyon NP (2 full days)
Day 17 – Drive to Arches (5-hrs)
Day 18-20 – Arches NP / Canyonlands NP (3 full days)
Day 21 – Drive to Rocky Mtn (8-hrs)
Day 22-23 – Rocky Mountain NP (2 full days)
Day 24-26 – Drive to Sandusky, OH (22-hrs)
Day 27 – Cedar Point Amusement Park
Day 28 – Drive to Rochester, NY (5-hrs)