If you are spending the night in Moah, try to visit Arches in late afternoon to get a feel for the place, then head NE on Rt 128 to Castle Creek Winery for dinner. https://www.castlecreekwinery.com
. Try the award winning Outlaw Red (reminds me, I've got to order another case). On the way back to Moah in the dark, they may be lighting up the cliffs with powerful searchlights. Very eerie. Then get up before dawn and go back into Arches to watch sunrise at the Natural Bridge.
My photo album of a car trip through Utah back in 2008 is here: http://billduncan.us/albums/vegas-to-durango/index...
You're right - so much to see and do. Big secret: the state parks can be just as exciting as the national parks and not crowded. Ask your innkeepers -- they know the best places.