Didn't teamwork feats didn't benefit only those who had them, in this case the commander and the troops would have to have the feat, or am I mixing that up with another similar feat type?
Teamwork feats usually rely on both characters having it, which usually make them...very not worth it in almost all cases (it's an ability that costs two feats to use, and can only be used with other people with the appropriate feat are near you). The commander's ability grants a teamwork feat to the entire unit, making them actually usable.
Escape route, Shake it off, and Spirit of the Corps look like the most useful from a quick glance through, Volley Fire for our crossbowmen, Cavalry Formation for our cavalry, etc.
Escape route in particular lets squads cycle injured soldiers out from the front line, and the fresh soldiers in to lengthen their staying power. Shake it Off would mean, in formation, almost every soldier would receive +4 to all saving throws (those on the very end of the line, in the corners, will only receive a measly +3
). Spirit of the Corps would let our area limited morale effects extend another 10 ft down the line in each direction in a limited fashion...
I'd go for Escape Route as default for Centurion level officers, with Shake it off as the one commonly used by Captain level officers (since it'll only come into play against magical threats).
