I've just added a bunch of new base designs for use with King and Parliament and To the Strongest!
The extra infantry files can be added on to the FK&P1 base (shown below) to make wider elements, or, in the late Century 17th, to add extra files of grenadiers to the flank of the battalion. The holes fit 3mm diameter rare-earth magnets.
…and here's a unit I based with the system. The idea is to break up the usual straight lines with a wavy outline that blends better into the base cloth.
…there is also an equivalent cavalry base, above, that can be added to troops of horse or used for singly-based miniatures.
Finally, the above irregular bases are primarily intended as casualty bases, but I also find them useful for small terrain pieces, flocks of sheep, and so forth.
All the Batbases can be found here (on that page and the following page).