Our DS was a successful re-applicant, who went to a 4 year college, pursued engineering, and also did NROTC. I can tell you what he learned during the process.
I think the most important thing is to mimic the Plebe schedule as closely as possible and do well (ie. >3.5). That means Calc, Chem, History and English along with Naval Science NROTC class. After getting the TWE, DS visited USNA and met in person with his admissions rep. He was strongly advised to take the classes listed above, which he did. He was not a D1 athlete however.
The other thing that was important was to re-take the SAT or ACT. Even though our DS has above 700 on each section, he tried again and raised his scores. That stands out and shows commitment according to the admissions rep. The sticky thread on re-application has a lot of great info, make sure DS understands it all.
If your DS is successful on the 2nd try, at USNA he would need to take 18 credits, along with all the military tasking AND the load of being a D1 athlete, so he needs to prove that he can handle it.
I would strongly suspect that if he does well in Calc, Chem, History and Naval Science but skips English it would be viewed negatively - how much so nobody knows.
There were several re-applicants in our son's NROTC unit who earned appointments, but there was one who did not, even though he was previously waitlisted AND earned a 3.9 gpa at a very good college. Even if he didn't win his slate, he seemed a sure thing for the national waiting list. In trying to understand why, the only thing they could figure was that he didn't take the recommended classes.
I would strongly recommend reaching out to USNA admissions and schedule a meeting or call with the rep. He/she will be happy to go through DS application from last year, explain where he may have come up short, and what should be improved. They will also provide very clear advice about college course load.
Best of Luck!