If it's really your dream, do a year of self-prep at Marion Military Institute.Just received my rejection from the USMA this morning. I contacted my Regional Commander about the possibility of the Prep School as I had a low ACT score for math. Besides my ACT scores(composite 27), I did well on my CFA, had a nomination, high GPA(3.94), and captain of two HS varsity sports teams. Unfortunately, my RC said that the Prep School space was very limited and that there was not much I could do.
It took DS 3 years applying to SAs. Once he attended MMI, he received appointments to all three SAs that he applied to.
It's not a guaranteed path, but if you really work incredibly hard, you'll have huge advantages with MMI. My son is in Plebe year at USMA and is glad he didn't get appointment until he had the year to get ready at MMI.