If you want something larger than skirmish or want to double up, then the old Command Decision title Over the Top works well. Figure scale is 1 stand + a platoon (40-50 men). Perfectly possible to use individual 28mm figures as a stand, without compromising ground scale too much. If you use one 28mm figure equals one stand then a battalion is about 16 or so figures. That's what I did some years ago. Just use different figures to represent different stand types. Inf stands are standard rifle armed stands, Command Inf are NCOs Pure Command Officer figures. It's an excellent and very playable game, like all the old Frank Chadwick products and you can readily play brigade sized actions in a few hours. Has a good selection of scenarios, army information and a large 'bathtub' campaign for 1914.
If you search around you should find a copy secondhand.