I had an ER nurse in a class. I noticed she kept taking all head shots. Her response when asked why, "'I've seen too many people who have been shot in the chest putting up a fight in the ER." Point taken.
The NRA certifications are of little practical value. They do have marketing value in that some states recognize them for carry licenses/permits.
You will probably need an instructor certification to get liability insurance.
I can't speak directly about the USCCA certifications, but based on indirect evidence, I would rate them similarly to the NRA value.
Rangemaster is the tops for actually preparing students to walk about armed. As you already have experience with CSAT, completing their instructor course would also be a consideration.
I had an ER nurse in a class. I noticed she kept taking all head shots. Her response when asked why, "'I've seen too many people who have been shot in the chest putting up a fight in the ER." Point taken.