I think our best formation based strictly on getting the best 11 on the field is a staggered 4-3-3 with Pulisic playing more centrally, in something close3 to 4-(1-2)-(2-1). It allows plenty of mixing an matching of the younger guys on the wings, which if we are being honest is easier than finding another WC level #10 for 2022 or 2026
It's not our best offensive or defensive set because it relies on CP being able to be effective with the ball in the center of the park. Something he has yet to show consistently that far from goal. It also requires McKennie to be more defensive minded as CP is not a good two way player and can't be counted on covering if McKennie goes forward. It does allow Dest and Acosta to play fullback, which might be our best two.
You could also play McKennie or even Reyna in that role, keep CP on the left and back fill with Acosta next to Adams in a 4-2-3-1. I'm not a fan of the 3 CB lineups, even in stoppage time. Why put more of what we don't have on the field, ever?
...............................Striker
LW...................................................................RW
.................Pulisic
.......................................... McKennie
...............................Adams
.........LB...........CB...............CB.................RB
.................................GK