There's enough sand in Stagecoach that anything less than 2.2 tires will be pretty unpleasant. You could probably route around those spots but overall I don't think a CX bike like the Straggler will be much fun. I don't think anyone on here has any experience with Baja Divide yet since it's not completely released and the first full through ride is this January. There's a lot of good replies from the creators on their website:
www.bajadivide.com. But even they suggest 2.4" tires minimum.
Have you thought about the White Rim Trail in Canyonlands? I don't know a ton about the trail conditions that time of year, but from a temperature perspective it should be awesome. And definitely a polar opposite of BC terrain.