I could adapt BFG to this, but I have lots of ideas that just don't match. This will not be a BFG clone, it will be a game of its own. It also means that should there actually is interest, it can be sold (if GW can try to sue someone for writing a book with "Space Marine" in the title, I'm not taking that risk).
If anyone has played Guns of Icarus, or Guns of Icarus Online, it is one of the heavier inspirations for this game. It is of course not going to be a tabletop port of GoI, because there's lots of things I'd have done differently.
I'm going to leave this thread open for its original purpose of seeing if there's anything on the market, and start "developing" in a different thread. Will link here once OP is written.