It's a decent prototype.

However, I felt like the progress is insanely slow. I don't know if that's how it's forcibly supposed to be played, like missions of 20 or 30 minutes and just leave it running on a second monitor? other than that you'd be stuck with 1 or 2 minute mission to get a tiny amount of coins.

Maybe I'm missing something? upgrades don't seem to be very significant and other ships costs an huge amount of gold which I don't even know how to get.

I'd add the option to make it flexible so if a player wants to actively play the game, they can, but if they want to leave it on a second monitor they also can. Or maybe a x2, x4 and x8 speed?

Still, it's a good base.