SS on Steam will certainly help to spread the word and draw in more potential customers which means more $$$. Considering game quality even now and that it doesn't have any solid competitors, even despite long periods without updates, game will still be praised, I'm sure. There will be some bitching on forums and reviews, but general public will be content with the game, that considering how much real broken trash has been shoved into Steam, it really will shine like a gem. I play 0.72a and it really doesn't feel unfinished, though I have played some EA games, and they were really lacking compared to this one. On a side note I don't think every game should have some kind of a goal, victory conditions and etc, balance is also arguable point, because we aren't talking about competitive muliplayer RTS or something. It's just a sandbox in space, and there are also tons of missions that I haven't even touched yet. Definitely NOT lacking in content especially with all these beautiful mods we have.
But tbh, Steam sucks balls, I like no DRM platforms way more, SS MUST be on GOG no matter what.