These are some great ideas other than the kitty litter... not seeing how that will help in sand. Great for sopping up leaked oil if you tear open your oil or transmission though.
Gary mentioned above about crossing washes. This can be a much bigger deal than many realize. Some of these crossing points are just steep enough that you can get really hung up either dropping in or trying to climb out, and if that happens it's usually not something most folks are prepared to extricate themselves from. Also, a passing storm far from your location can cause a flash flood many miles away washing away your exit road.
Watch the weather, presurvey your route if possible, be as prepared as possible including jacks and timbers if you really are heading into remote desert country.
Just my opinion after a few years of desert boondocking. Have a great trip!