While all the factors are important, if you had to pick one single factor that you could get perfection on, without a doubt it would be ACT/SAT scores. Academics are the most weighted part of the application at all of the academies, by a huge margin, and the test scores are half of that, or all of it if the schools don't rank. Other than the CFA, the other factors are assessed less objectively. That does not make those factors unimportant. They are quite important. But the test scores are measured on the same standard for every applicant. A 36 on the ACT will not get a kid in all by itself, but neither will perfection in any other factor. The 36 ACT though will get the attention of those deciding, and on the WCS nothing else will count for more. Most other factors aren't even close.
People frequently diminish the thought of the test scores meaning "too much", emphasizing that they are just one part of the equation, which is true, but don't lose sight of reality either. The academies want bright, accomplished, and athletic kids who are strong enough to survive or excel at the academy, and to learn to be leaders. The test scores are an imperfect but pretty good instant assessment of academic potential. The daily chalanges for most academy Cadets/Mids are with academics. The CFA is a pretty good snapshot of how fit a kid is. But the CFA is only worth about a third of what the test scores are worth.
Most important factor? ACT/SAT.