I view the footmen in stonehearth as like the generic guards a fantasy town. The idea is, is that the footmen guard the town while the upgraded versions of them, like knights and wizards and so on, would be the heroes that went out and had adventures.
I feel like the footmen should be weaker than the other combat classes rather than be the dps class like it was explained in the development blog, and instead the footman captain is the dps guy. It also gives a cool feel to have your footmen be led around by a captain, and you can give restrictions on the requirements of being upgraded to a captain, like there need to be 4 footmen per captain.