Here's how I'm thinking of doing my 6mm AWI figures:
Piquet normally uses four stands, so I'm planning on four 40x20mm stands, with two ranks of 8. The right-most on the front rank will be an officer, and there will be a drummer in the rear.
For cosmetic purposes, I will include a 20x20mm command stand in the middle. In the front rank: line, officer, drummer, line; in the rear: line, regimental standards, and line. I will try to put a colonel out in front, as well.
That works out to be exactly one Baccus package, $6.60, with an extra command stand (which, you can see, I don't have yet). At around 12 units per army, it looks like about $100 per army or $200 total. That's about in line with cheap 15mm costs, and definitely cheaper than 25mm.