Riflemen should give you a sound advantage in range but a lower rate of fire. I don’t know about European Rifles, but the American ones being locally made lacked bayonets.

Depending on the ammunition carried they could definitely be your most powerful anti-infantry weapon while holding the line infantry in reserve until the great bayonet charge! Then perhaps they would be used as fallow on units aiding in the grand rout!

I am fairly sure that some of these tactics will prove to be ridiculously optimistic when the game gets here, but it gives us mental exercise while we wait.