... I'm a worrier....
This is your biggest hurdle to overcome. One of the great aspects of riding (for me) is the uncertainty of what might happen. Whether it's down the block to the store or halfway across the country, there will be risks and unexpected situations to overcome. I believe the challenge of overcoming these obstacles by luck or our sheer wits and skills is one of the pleasures that drives most of us. If you're looking for a guaranteed
safe and comfy ride for your trip, I'd suggest you take the car.
I'm going to let you in on a little secret. There is a ton of LD BMW riders in Mexico. Dating back to the late 60's. That would be worth investigating IMHO.