SSG Eval board. What will have the most bearing on someone being at the top of the list?

Look up your Branch's board AAR. They will tell you how the board evaluated Soldiers, what made some more competitive than others etc. The Army isn't really taking the ACFT yet, which means not everyone will be evaluated on it, which means it will have very little bearing on the board until it is mandatory

Being that the ACFT is the Army's "New toy", I feel safe betting it will count A LOT, especially since PT score has always been a legitimate factor. Other things I believe earned my P status in this year's board were SHARP 80hr cert in addition to a large variety of schools, and NCOERs. Just try to be the best at everything, eventually you'll be the best at some things, and that should be enough.

Right now it will mean little to nothing. It's not yet official, and after this FY20 trial period, they will need to look at the performance data and decide if and how to tweak things. If I were a betting man, I don't think it will be a thing until sometime in Summer 2021 at the earliest