I rode the national enduro in Phoenix last year for my first desert race. I grew up riding in new england and have since moved to the midwest so colorado, utah, and the southwest aren't that far now.
Anyhow, I basically upped the compression a couple clicks front and rear, upped the rebound one click and went out and rode. Not knowing what to expect, I just figured a little higher speeds and less roots and rocks. Boy was I wrong about the terrain. Just about a little of everything. Bottom line was I didn't really think m,y settings were off that much. I would spend a day riding before a race to see if you can get the suspension dialed in better.
As for gearing, I didn't notice a problem with mine. Might have wanted a little more top speed bit for one race I could live with it. I did change jetting for elevation (4-6K for the enduro)
As for good races. The national was cancelled this year. Best in the desert is a good one but I think that is this weekend or next.
Definitely try it and enjoy!
Bish