Can't help but to get a bit off topic just one more time.
I'm talking music but I know the thread is about sfx....
Last time, I promise.
One guy that always gets me jealous by being able to produce such fantastic scores as those for Undying & Return 2 Castle Wolfenstein...
Bill Brown.
D@*n that guy!
For if you want to listen to it;
Undying Theme RTCW Theme
Back to sfx, rts Homeworld 2 was incredibly good. (incl gameplay, graphics etc).
(space-warfare game....)
The Music was only thematic on certain points, important events.
Otherwise the music would be kind of an ambience track, with a "space-feeling" to it, reducing the need to add sounds that would exist in vacuum.
So a thin line between sfx/foley/music here.
Instead, most of the sfx to create 'that space feel' you'd still need for such a game were linked to the spaceship you'd be controlling.
So each unit has its own spacy sound.
This suggests that everything you hear comes though an imaginative intercom or something like that (provided the mics & speakers in spaceships would be of recording studio quality;-)
For me this worked great since I always get distracted by the abundance of outer-space combat sounds in these games.
There's always that "What kind of 'space' is this anyway??" thought in the back of my head
If we'd have sound in space, we could use this little baby as a giant tweeter instead of a radio transmitter.
"HELLLOOHOOO!!! ANYONE OUT THERE???"
Wouldn't you like to hear that woofer btw...?!?!