I'm bummed to think about BB not being in Moab, there is a lot of built in logistics, contacts and information that only comes from the years of the event being in the same place at the same time.
If it were to move one option could be Montrose, Colorado. There's a great deal of I'm not sure what the status is of some of the what used to be harder trails on the west side of town is?
The opportunity for High country Colorado trails is just down the road in Ouray, most of these are considered bucket list trails and are easy day trips from Montrose, the trails on the west side of town offer up harder options all the way to full buggy eating hardness. The black canyon of the Gunnison is 30 miles away for family site seeing adventure etc. Then Grand Junction with bangs canyon and 21rd aren't too terribly far either (not great for a day trip but maybe ok for a stop going to or from?).
Montrose is one of the larger towns in western Colorado which allows for several hotel and I'm sure RV park type options.