Hopefully, riding during the weekday will help with the spring break drivers. Perhaps riding in the mornings will have most of the drinkers sleeping it off.

I've taken a look at some of the CO and FM roads on Google and may have a back up route, just in case.
77 looks to have pretty wide shoulders that seem to be in good shape until getting past Riviera. Our turn-off for the Beach house is before Riviera, so we'll see.
The FM and CO roads look pretty rough with no shoulders and street view showed at least a couple speed limit signs for 70 mph on them.