As to the note of more weapons, it is not hard to add a dozen weapons based on the current weapons. Merely making stronger and weaker versions of what is in the game already, would take me, maybe an hour or so. I added 4 new types of shields, that cover more or less area, have stronger shielding and whatnot. The dev has already stated he believes multiplayer for this game is something he would like to bring back. The game initially did have multiplayer in the game, and you can share ships with other people which is a very, VERY niche form of multiplayer.
I think many people would agree that a coop mode, with the option to fight one another would make this game something that stands on it's own. I don't know if the dev plans on adding this game to Steam once it is at a stage he feels it is something people would pay for, but I was shocked that this was a free game. I am willing to add my skills to adding mods, and adding more features to the game, as long as the dev continues to update the game, which he shows no sign of stopping.