I have 3 things to say.
1) This game completely got me by surprise. I didn't know that a game like this was being developed, and ...
2) if it weren't for the fact that it was posted on a pirate tracker, I would never gotten here. (let the paranoia begin)
3) The fact that I got here is great, because I can now support you guys, by preordering right now.
But I too you prefer to buy it somehow through Steam. I bought for example Gratuitous Space Battles through BMTMicro, before it was on Steam. But when it got released on Steam, I didn't get a key to activate it. The fact that to update I had to manually download the installer, was something very annoying. I might be still enjoying the game it if I had received a Steam key to avoid that. But since I didn't, I was excluded even from the choice of buying their DLCs.
I'm right now buying Starsector through BMT, but I really do hope that the devs try their best to give us a key on Steam, like many other devs did, and do not alienate us on the future.