If you plan on seeing southern Utah, there are so many places to see that your entire time could be spent there and still not see everything. My favorites - Zion, Canyonlands, Goblin Valley State Park, Dead Horse Point State Park, Arches. I have a journal & photos of the area as part of my 2011
If you enjoy caverns, I suggest a stop at the Caverns of Sonora in Texas. The most beautiful cave I've been to. Their web page
. My photos
. There is a campground at the caverns.