I've been working on a mercenary company that specializes in anti-piracy and recapture operations.
basically a force built to 1)track down stolen ships with the intent of boarding them and reclaiming them for the client, and 2)find pirate bases and make like the Beach assault scene in 'Apocolypse, Now!' only with battlemechs.
so each lance is built as a reinforced air lance, with four mechs, two ASFs, and at least one platoon of infantry, preferrably two. the ASFs would have troop compartments.
three of these lances combine into something like a battalion combat team equivalent to a squadron of ASFs, a company of mechs, and two companies of infantry.
I would imagine dropships like the Octopus would be ideal for privateer operations.