Understandable and I agree that the sound effects should come first.
Customizable playlist would take the work of creating ambient music/effects away from the game makers so they can focus on core stuff, because a whole cottage industry would pop up where community members would create ambient-noise and song MP3s for everyone to try. You'd see entire themed MP3 packs for any situation with common elements shared among the related tracks. It would be self-regulating, because copyright violators would be discovered and voted down, and original creations would be promoted. You could run an MP3 through SoundHound to find out if it is original with the contributor or if it is an invalid contribution.
Then, and this is where it could get interesting for the developers, the community could vote for the best theme packs, and then the track creators could donate the rights to the entire soundpack to the game developers/distributors who could then package it up and sell it as the official soundtrack on iTunes. "Get StarMade Ambience Volume 1, available now!" And it wouldn't just stop with the top winner. Runners up would also have the option to offer up their packs which could then be sold as Volume 2 and so on. And as more sound packs become available, new votes could take place, and more ambient track albums could be sold to support the developers.
To clarify, the option should be there to create a different playlist for different situations, such as spacewalking, combat, planetary operations, planetary walking, building ships, building stations, flying, and shopping. Then a person can create a customized playlist for each situation, and whenever an event is triggered, their current playlist is automatically replaced by the one they picked out for the new situation. In other words, when the player, cruising in their spaceship, is targeted by a pirate or actually hit by weapons, the "flying" playlist is stopped and unloaded, and the "combat" playlist is loaded and starts playing automatically. It wouldn't be as smooth as some of the AAA-title on-the-fly ambient music composing stuff that you see in really advanced games, but it would be easier. Plus, it might actually be better for many players, because they'd choose their own ambience without having to replace static game audio files with their own or install an ambience mod to do it for them. A lot of people have playlists ready to go, and if the built-in player could load up those playlists, it would be an easy win.
This is giving me an idea for another big community contest after the spacestation contest is over: audio effects. If only to help out the developer, so they don't have to come up with every audio clip by themselves.