This was what we did on our trip two weeks ago. We actually didn't even do mornings in the parks. We slept in, went to a water park or swam at the hotel in the late morning, hung out in the room until 5-6 and THEN headed into the parks until usually 10 or so. We got plenty done. We had our 3 FP+ lined up back to back and were able to do rides in between the return times. On our last night in MK (a Friday), in 2.5 hours we did NINE attractions AND we ate dinner (Speedway, Dumbo, 7DMT, Astro Orbiter, Small World, Aladdin Carpets, Teacups, WDW railroad, and TTC). We could have stayed longer and done more, but my youngest son has sensory issues and insisted we be OUT of the park before fireworks started each night.
This will be our "go to" plan from now on in the summer. It was wonderful. One night at Epcot, we rode everything in Future World and had dinner in 3 hours!