I always wonder/am reluctant what to tell folks they need to score. Guess it depends on other aspects and of course higher is always better.
Well... first off, I am not going to say your DS had any flaws!
I maintain that too many people put too high a factor on the physical fitness test. It is important but I can't believe it is any more important than leadership, schoolwork etc. They are all equally important. I want to believe that the selection board looks at the entire person when making the decision.
Note I said it was just as important as the other portions - not less so.
Based on what I have seen over the last 3 years along with discussions with my son (current NROTC MO student) I would say that the average scholarship winner is north of 250 points in the application PFT. I am sure there are examples of winners with lower (not much) and certainly higher.
I might note that my son reports that with less and less scholarship winners reporting to his unit each year, the average score for these freshman has been going up. Makes sense.
As you state, the higher the better for sure. That goes for GPA, ACT/SAT scores, leadership roles, etc.
Pima points to a great way of thinking about it. Focus on 300 points (the max) rather than a minimum.