If you're going to be trailering to places like Pink Coral, you might also want to look into the Hogs canyon trail system just north of Kanab, right by the turn off toward Pink Coral as I recall. You also have the Peek A Boo trailhead just north of the Best Friends Animal Sanctuary. From Peek A Boo you can explore a neat slot canyon, and one of the trails/roads swings by a cave with a little lake/pond in it. The Hogs Canyon system has a good mix trails ranging from easy to quite challenging. Pink Coral is pretty much just sand dunes type riding, which I find fun for a day but prefer to have an area where I can mix it up. I prefer Sand Hollow just outside of Hurricane Utah for the dunes in that area as you can ride the sand for awhile, then get into some very challenging technical riding on the slickrock.
As has been mentioned, carry a good map, and watch out for anything that might have been placed to try and discourage ATV use. We spent a week in that are riding in March and saw a lot of illegally placed trail closure and wilderness boundary signs, along with assorted barricades. (We verified they weren't legit signs with at the BLM office) While I've sometimes seen certain groups photographing riders during group rides and jamborees, for the first time this year we saw people photographing boondockers on forest service land where it wasn't marked on the motorized use maps as open to camping. We stopped and talked to them for a bit and they informed us they were documenting this "Abuse" to try and get the roads closed in the area which in their opinion should be designated wilderness. As there are a lot of groups trying to shut down all off pavement travel in this state, please help us out while you're enjoying all it has to offer, and stay on designated trails so as not to give any credence to the abuse complaints.
Hope you have a lot of time to explore. We've been spending several weeks a year exploring Southern Utah and still feel we've hardly dented the possibilities.