We did a similar trip in 2021, about 10 days. Here's what we did:
Flew GRR to PHX (Southwest Air), then drove to Sedona (stopped at Montezuma Castle NM on the way).
Sedona (2 nights, VRBO condo)
-hiking
-Pink Jeep Tour
-Slide Rock State Park
Williams, AZ (2 nights, hotel)
-Grand Canyon (hiked a portion of South Kaibab Trail)
-Bearizona (zoo)
On the drive to Kanab, we stopped a couple of times to stretch our legs:
-Horseshoe Bend
-The dam in Page (I can't recall the name)
-The Toadstool hike
Kanab,
UT (4 nights, VRBO house)
-hiking
-Bryce Canyon (we hiked and did horseback riding)
-Coral Pink Sand Dunes
-Moqui Caves
-Best Friends (we had this on our list but unfortunately ran out of time).
-ATV tour to Peekaboo slot canyon - highly recommend!!! My kids called this "the BEST DAY EVER"
**From Kanab, the drive into Zion NP east entrance is spectacular! Do the Canyon Overlook Trail before tunnel.
Springdale, UT (2 nights, hotel)
ZION NP
-The Narrows - so amazing!!!
-The Watchman Trail and Emerald Pools Trail
My oldest son and I had planned to do the Angel's Landing hike (this was before the reservation system), but on the day we planned to do it, the chain section was closed for maintenance. I honestly couldn't decide if I was disappointed or relieved by that!
-I also ran the Vacation Races Zion Trail 13.1, which was so cool.
If hadn't run that race, we would have skipped staying the 2 nights in Springdale and stayed in Kanab, but I needed to be closer to the start/finish in Apple Valley.
Flew home LAS to GRR nonstop (Allegiant Air).
I wanted to stop at Valley of Fire SP on the way to Vegas, but my family was cranky and I was overruled.
Let me know if you want more specifics.