So my group is a little burnt out on fantasy settings and the idea that gets us the most excited is a good space opera type of campaign. Somewhere in the realm of Star Wars, Star Trek or Mass Effect. The biggest desire is a system with both good and varied character rules (aliens, robots), but also good spaceship rules. We want to have a lot of customizability with our ship, and have a good space combat system to use it in, while at the same time having a good system for character stuff like combat, exploration and etc. etc.
We've taken a look at the Serenity RPG, but it really doesn't do what we want in regards to ships, and it doesn't really have rules for aliens and whatnot as far as I've read. We have Eclipse Phase, but I'm not sure I want to try and hammer it's very specific settings and themes into what we want. Right now, GURPS is looking like the best bet, but we have some issues, mainly in the number of books we'd need. (Right now I'm looking at the two core books, the space book, the ultra-tech book, and a mess of tiny and overly expensive spaceship books (Seriously, why is a 42 page PDF EIGHT friggen dollars and why are there 8 of them?); and this isn't even the amount of variety I want.. we'd need to pick up books on robots, biotech and probably a handful of other things. GURPS also confuses me in that I'm not sure which version to pick up.
We kinda got supplement fatigue with all the various kittens in the D&D/Pathfinder litter, so if we could get a system that was just a couple of books, that'd be nice.
Posts
You can find the rules in his OP here: http://forums.penny-arcade.com/discussion/167453/where-no-man-has-gone-before-episode-1-pilot-scene-2-onboard-the-uss-anansi/p1
But also D20 Modern + D20 Future worked great for a Deadspace Game we ran a couple years ago. D20 Modern could pretty much be coined as D20 Generic. There is little you can't do with the system with a little homebrewing.
Critical Failures - Havenhold Campaign • August St. Cloud (Human Ranger)
Also, have you looked into Traveller? Specifically the Mongoose version sounds like exactly what you're looking for, and almost all of it in the Core Rulebook--very customizable ships, detailed-but-not-overly-so exploration/trade/fighting rule, and a wide variety of character types. The only things you might need supplements for are if a PC really wants to play an Alien (they have modules for most other species out already, or in development), or a Robot, which gets its own sourcebook.
Of course, because I always recommend it, I'm going to jump in and also recommend FATE. The great thing about FATE is it's designed to use the same rules at the personal scale as the ship scale as the cosmic scale, meaning you can customize it however you can customize a character.
And then, of course, Mutants & Masterminds, even though it's billed as a Supers game, is secretly the most customizable, easiest-to-use universal game system is existence (in my opinion, it blows GURPS out of the water). It also has very detailed vehicle generation and great personal rules.
And the best part about FATE and M&M3 is they're both free.
A solid rules set with one of the best space opera settings ever, Star*Drive. That book was joy to read. It's been out of print a decade (it was a TSR publication) but I think you can download *.pdfs from like rpgnow.com and other pdf sellers.
Ashen Stars has a very Star Trek-type flavor.
Combat is quick because combat will kill you dead. It's a not a super-heroic space setting like, say, Star Wars might be? SWN will kill you if you do dumb things, so I've found fights are exciting, quick, and uncommon. Star ships and such, are obviously included and use a really straight-forward customization system of available power and physical space for building a vessel.
And honestly? The game is 100% playable with the free PDF. You can buy the book or PDf, and the only difference is you'll receive a chapter on androids, mechs, and a social-evolution table for seeing how a government changes after interstellar collapse. Handy? Yes; hardly vital.