Searching UT, you are in camping heaven -- it takes us two days of hard driving to get to where you are, and Utah has more great remote camping than any other place I have ever been (and that includes Colorado). Colorado is beautiful, don't get me wrong -- but it is much easier to find true silence and solitude in Utah. (Not with hookups, of course, but boondocking is priceless.)
Once you are retired, you are all set! The only trick is making sure that your trailer is four-season ready. Southern Utah is great for winter camping because although it is cold, there is usually not too much snow -- just enough to add contrast to those red rocks.