Lots of threads on this subject, and the answers can be varied.
If you have a set travel pattern, say winters Az, SoCal, and summers Id, Wy, Or, and maybe Wa. You could get a new plan in Nevada, Make the University med center your primary care facility and your electronic records are available both in the southern region from Vegas, and up north from Reno and several small clinics. And from those other states your still always within a days drive to your home system.
If that doesn't help then select your plan based on flexibility in Dr. visits, but with the med insurance industry still evolving it's hard to say where to go, plans change, companies want to force you to their preferred providers, flexibility is the last thing they seem to want to offer.
Fl. has been mentioned here several times as having better plans available for those not on medicare, You may want to look at Escapees.com for some guidance, they have quite a bit of material helpful to fulltiming, and have Fl, along with Tx. and SD as states they follow the changes most closely in.
At any rate get digital copies of your med records before you hit the road, having the information available is a timesaver when you do have to go someplace new.