You can use that... marsflier was it? Its so "unique" (i havent really seen more than one person flying one) that you will be identified from.. long distance.
The one planet with abundant alien life already in the freelancer universe is Gaia.
Instead of going for the "aeons old ancient superior tech" type aliens, why don't you go for something from there that has managed to escape into space--perhaps having some very mild ability (chameleon like maybe) that has allowed it to stow away on ships and study the crews and learn to operate the technology.
They might need a human go-between--maybe someone in partnership with them, keeping them secret.
What would they do though? you also have the dilemma of inventing a culture or tech that isn't a universal part of the mod. it can't dictate new play realities to everyone else--it has to be limited and somewhat unique.
I'm not going for super-race either, nor super technology =P
I'm really basing it off of the zerg/aliens, as shown by the signature... they'll be an organic race with little knowledge of technology, but scary looking and very lethal in hand to hand combat.
The idea I was originally going with is that a few of them managed to get onboard an exploration ship - maybe via eggs or soemthing that were brought onboard by the explorers running the ship - and then 'hatched' or came to life and started taking over, slaughtering crew members and keeping only a few of them alive to run the ship.
And as for 'what would they do' - it wouldnt be some galaxy-spanning empire like the k'vosh/c'tan. The infected ship would simply drift through colonized space, scaring the crap out of people and boarding/infecting other vessels.
It's more of an isolated incident than a full on invasion.
Not too bright, mean in hand-to-hand, can handle more bullet holes than I've ever seen, and ties ropes around peoples necks to make them work. If this isn't it, I don't know what is.
I do believe that would be a Brilliant Alien species to be. Long life, prey on humans but look just like them. One person called them Space Vampires:rolleyes:
If you intend to go ahead with it all, what about a small group? I'd jump at the chance for it if possible?:)