But, maybe I missed it...when are you going? It is still very much winter--and all that means--over your route.
1)some suggestions---are you definitely camping? Moab can be a real pain if you are hitting it when the tourists are...just sayin'. Been there only twice, but have stayed at the Rustic Inn and it was fine. A bit off the main drag, but that means lower price, not lower quality
The Islands in the Sky part of MOAB is pretty much across the street from Arches. The other part (needles? iirc) is about 45 m south.
Look at Potash road from 191 up to Islands in the Sky.
the La Sal Mountain loop is worthwhile, and 128 is gorgeous.
There's some good riding up toward Vernal, look for the squiggly lines.
2) Coming out of Co into Utah, great road is CO90 to UT46 Paradox Valley and Bedrock
3) I would head over to Cali across NV via the Extraterrestrial Hwy, skirting the northern edge of Area 51, look for the "Mailbox" and the Little Ale'Inn, just for "Americana" sake, then head down. If you have time Ca 120 is a lot of fun toward Lee Vining and Mono Lake.
4) Don't miss the winding road out of Artist's Palatte in Death Valley...it's like your riding a winding hallway.
5) Red Rock Canyon, just outside of LV, is worth a couple of hours to do the loop
6) If I had to rank the Parks along your way I would place Canyonlands/Arches, then Bryce, then Zion
7)Another good motel in Utah, is in the Zion area in Mt Carmel Junction, the Best Western w restaurant on site. and UT 14 from Cedar City to 89 is a fun road, but usually has a bunch of slippery tar snakes.
7) on your way back, if you can swing a route along N AZ, riding along the Vermilion Cliffs is sublime, US 89a. 89 on the north side of the cliffs isn't bad either, but everyone needs to see the Vermilion Cliffs at least once. Page is a cool town for an overnight and it is close to the Horsehoe of the Colorado River--it's in LOTS of photos, and you can get quite a view. It is also near some famous "slot" canyons, like Antelope and Secret (I can rec Secret with the Hummer Adventures?? tour people. Do the "photo" tour to have it to yourself.
Hope this helps
and if you can come back up through NW Arkansas...