What RPG has the best spaceship design system?

[Michael Thayne]

I've looked at a lot of RPG spaceship design systems, and have never been quite satisfied with any of them—particularly when it comes to the handling of space combat. I'm coming at this from a position of not minding complexity much, but being deeply annoyed by things that make no in-universe sense. Here are the systems I'm familiar with:

• GURPS Vehicles 3rd edition. Like I said, I don't mind the complexity, but in spite of all the attention to realism, there are some definite wonk elements, like the laser rules.
• GURPS Spaceships 4th edition: has a lot going for it, but the lack of support for custom missiles/drones less than 10 tons (and the fact this decision wasn't wholly arbitary—which becomes apparent when you try to home-brew a fix) is a real problem. The limited choice of hulltonnages also isn't ideal, though IMHO not as bad as the hard lower limit.
• GURPS Transhuman Space Classic: being specific to one setting has major benefits to the point that I struggle to point to any really fatal flaws, but it is very setting-specific and the range of what you can do is limited in some ways.
• Classic Traveller: a major influence on probably every subsequent sci-fi RPG, but it's hard to get something right when you are the first person doing it ever, and it shows. Numerous tables that almost follow a pattern but don't, and IIRC other wonkiness.
• Alternity: For those who don't know, Alternity was a short-lived RPG by TSR whose setting got recycled as d20 Future. Actually my first sci-fi RPG ever, and the source of my handle on these forums (my real name isn't Michael!) I don't actually remember much about the spaceship design system, except that in retrospect the Traveller influence is obvious, and unfortunately the core mechanic (for the entire game, not just space combat!) is pretty wonky.
• Squadron Strike: technically a tabletop wargame, I mention it here because I really respect the author, Ken Burnside. Unfortunately, IIUC the ship design rules are so complicated they exist only in spreadsheet form, and I'm not sure the ship point costs are meant to be economically meaningful rather than a game balance mechanism.

I suspect the thing I want is a more recent edition of Traveller, or maybe 2300 AD, but I don't want to plunk down $50+ on anything before soliciting some opinions. Note that I already understand Traveller 5 is quite complex, and while that isn't necessarily a deal-breaker for me I know it can be hard to make every part of a really complicated game work together with every other part in the intended manner, which is probably the biggest reason I haven't bought it yet.