Fly yonder and shoot that... its hard to see how they can add too many extra storylines but perhaps you should send them an email with your ideas for more plot?

I Played another Game For Yaers, and was Never Bored with it. FL. By Digital Anvil was Great. You could also Up-Grade your Ship/Equipment in that some, and Had to Move Through a Larger Galaxy into six or seven Zones of Groups of Stars each with about Two To Four Issues to Resolve in each zone, Before you Could Move On to the Next Mission Segment. As You Moved Up The Scale To The Next Level of Effort, The Combat Got Exponentially More Difficult. Final Survival was a Serious Fight in it.
I Finished This, (Rebel Galaxy), in around Three Days?? and felt let down at the end.
10 to 12 Star Systems is a bit small... Small Cargo Bays Make Mining as a Base of Operations Almost Useless... There were some Mining Areas in Fl That were Lucrative. This Has Some Value, but very limited by Cargo Bay Size.

so get in good with the merchant guild and purchase bigger cargo bays... thats what I did.

he story isnt the longest, and not complicated at all.
But you cant do much more after that. It is small game, and as such should be reviewed.
Maybe if there was Rebel Galaxy it will be resonable to ask for more quest with story.

Can't do much after the story is ended?

The meat of the game is exploring, doing various standard missions (There is a decent variety.), trade, mine, chose militia or pirates, test various equipment and ships and so on. The story missions is just someone nagging at you "Do this now!" that are done when you want to get rid of them or are curious about how the story will play out.
It's a sandbox game so go out and just fool around and have fun.

I was thinking that this is 5$ game made by 2 dudes.
What you gonna expect?
I think it is fair 10h of gameplay, and quite fun when it last.
It leaves with hunger for more, but you got what you paid for.

It's ten hours if you go a straight path through the story missions and doing other missions and stuff to upgrade your ship just enough to get the story missions done.
If you do that yeah you're going to think the game is short and doesn't have much to offer. Go off the beaten path and you'll find the game grows very much.