It strikes me as a bit odd that people keep mentioning boarding crews and marines and soldiers and strike teams occupying their ships.
How exactly do these military personnel get from your ship to the target? Last I checked there's no such thing as star-trek transporter pads in freelancer, nor do ships as small as gunboats or cruisers have the capability to carry a boarding shuttle/freighter. You're not going to be physically latching onto the airlock of an enemy ship in battle, either, not unless you manage to completely disable their shields, weapon systems, and engines - all somehow without damaging the ship to the point of structural breach or complete destruction.
The only ships I see ever having the need to carry marines or similar military personnel are Carriers, Battleships, and landing craft for assaulting planets - and the latter dont really exist (yet). Carriers and battleships both have the ability to, in-rp, carry a shuttle/freighter for boarding actions, and even then those boarding ships can only be used against another battleship or carrier (because those are the only ships large enough to have a docking bay for the boarding craft to land in). Even in those situations, you still have to manage to disable the shields and weapon systems of the enemy ship to give your shuttle a chance to land without being blown up or running into a forcefield surrounding the target.
All in all, I just dont think space marines really have a place in freelancer starship combat.