My best advice is to look at the AFA as an Ivy league education. Many of the cadets, and candidates had a choice...AFA or top tier colleges (HYPPSM, UVA, Berkeley, UNCCH, UIC, Notre Dame, etc), most had either AFROTC scholarship or big time merit money, thus cost was not a factor as much as one may think. Typically the decision came down to lifestyle as an 18 yo for the next 4 yrs.
The real difference between the top tier colleges and an SA is they are transparent regarding the admission process and how they score an applicant (aka candidate), colleges are secretive. They tell the candidate the percentage weight for academics, athletics, EC's, recs, etc.
The top tier colleges will also want to see that you aren't only book smart. They will want to see you have the whole package. Athletics, student govt/clubs (leadership), BSA, GSA, jobs, volunteerism, etc. while maintaining a rigorous curriculum will be just as important to them as it is to the AFA.
No admissions dept wants the 4.0 uwgpa, with 9 APs, 2400 SAT, but no ECs over the 3.8 uwgpa with 8 APs, and 2200 SAT, plus SC/Class president, 4 yrs on the FB team, NMSF, NHS, job and 250 volunteer hrs.
Besides the nom issue, the only real difference is the SA's state you need to show athletic ability by passing ALL parts of the CFA and be medically qualified.
If you were my child, I would tell you to take the most rigorous courses available. I would also suggest that you think about how to blend the ECs...killing 2 birds with 1 stone.
I.E. Job at Target stocking shelves is great. Job as a lifeguard shows athletic ability too. Job at the local hospital can also have unexpected volunteer hours. Job as a paid summer camp lifeguard for your church, BSA/GSA or 4 H, can fill 3.
I would also say as a long term poster, to make sure right now there is no medical issue. If you look on the DoDMERB threads, so many kids/parents here never thought there was a medical issue until they went for an exam. They never knew that a prescription med by their hometown doc would get them DQ'd. If you have been on meds for anything, including eczema this will be part of your process. Get in front of it now.