If you're picking a degree knowing you'll pcs every two three years, avoid anything with a state licensure requirement at the end
Learned about this so flagging it for anyone early in the process, a lot of degree programs that look perfectly reasonable online turn out to require state specific licensure to work in the field. Teaching, counseling, social work, and some healthcare adjacent tracks, the degree transfer fine, but the license doesn't, and rectifying in a new state after every pcs is a real job in itself. The programs that tend to hold up across moves are the once where credential at the end is either nationally recognized or employer-evaluated rather than state board controlled. IT, cybersecurity, business, public administration, emergency management, intelligence studies. These fields don't have a licensing board in a new state waiting to tell you that yours hours don't count.
Not saying avoid all of those fields entirely, some spouses make the licensure path work, especially if the service member's career is likely to keep them in for a longer stretch, but for anyone who knows they're looking at multiple duty stations in multiple states over the next decade, check the licensure requirements for the specific job you'd want at the end of the degree before committing to the program.