Freelancer would make a fantastic TTRPG setting and I'd be curious to know if anyone has played in or GM'd a game. If so, what system did you use to run it? Otherwise, is there a system you might recommend for a Freelancer TTRPG?
As an aside, I've done some reading on GURPS and feel like some scifi variant could work, though I'm hesitant to design something custom given the complexity and effort required to create a well balanced, enjoyable ruleset. IMO the biggest hill to climb is balanced, engaging combat - variables like ship speed, size, health, equipment, ect could be hard to manage without getting bogged down in crunch. In the absence of an existing rule set, and if others are interested in building a Freelancer TTRPG system, I'd be down to turn this into a community project.
I had considered what I would do myself for a TTRPG with the freelancer setting. My kneejerk reaction is the FFG Edge of the Empire game engine, mostly because the game integrates on foot content, vehicle, and capital ship content together relatively coherently. The system is not perfect though, it is unwieldy and uses it's own custom dice. But I have DM'd a game of it and played in it, and it's fun, and very narrative focused with a lot of neat tools. Here is how some of the stuff in the game looks. Hell, maybe I will write that freelancer module some time when I got a lot of downtime to work with. It'd mostly be reskinning assets and fiddling with some balance, and then really it comes down to how a DM can make use of the tools. Thankfully there isn't much lore I'd have to write myself!
Stargrave is awesome for some casual stuff, it's a skirmish wargame with rpg elements.
Also +1 to edge of the empire. I haven't played it myself, but I've heard wonderful things. FFG is generally a decent designer (their 40k stuff can be a little too mechanic-heavy though).
If you're looking to simulate ship combat, consider printing off some minis and picking up some rules for X-Wing TMG.
I already dip into Stars Without Number as a source of inspiration, and I've thought to myself on many an occasion that it could be super easily adapted to the universe. The rules provide just enough of a framework for a neato OSR-style adventure. A lot of it works right out of the box really, with a creative DM. It's just the setting information that would need some adapting to work seamlessly with the (many, and high quality) DM tools it provides.
The spaceship / space station rules are probably a little barebones for the sheer scope and variety on display in the actual Freelancer game. That probably needs some heavy homebrewing to match the video game thematically. For things taking place on-foot though, I'm absolutely in love with the idea of it.
I've set myself a project over the next month or so to get a working oneshot running, using the intro mission as a proof of concept. I'll update this thread with the results and some notes when I'm done.
I would suggest Mongoose Traveler. The only TTRPG where you can die in during character creation. It has great ship rules in my opinion. I found it quite difficult to play out ship battles with people in a any TTRPG setting. Minis are a great help!