I didn't want to say by any mean that this is not a good game.
It is very enjoyable indeed, but the replay value seems pretty low and the 'campaign' is terribly short and shallow.
It is cheap as far as games goes, but as a coffy breaker sits at costly. And the fixed campaign is a bit too shallow. It should be compared with said infinite space, which is worse as ship simulator but actually gets very different one playtrought from the other
Its worth it.
There are quite a few ships you can play. Due to early game mechanics, they all play differently at the start, and your starting loadout and abilities massively changes what you can do and what you will (plan on) buying as well as having unique subsystems (eg. Zoltan ships have a unique energy shield that blocks the first 5 damage (including missiles) and stops boarders).
For instance if you play the engi ship then you will focus primarily on drones, and damage weapons besides those are unimportant until you get to a point where enemies have like 3/4 shields each. If at all possible you will need to buy a drone reloader, and that will be your main focus at shops.
While the kestral starts with a basic weapon and a missile, while this makes you quite powerful, you will probably end up using most of your missiles at the start, resulting in large problems in zone two and three unless you get a alternate weapon. In addition it starts with 5 weapon power, allowing you to field two good weapons from the start.
And that's not even covering all the different ships.
In addition, each ship has two different starting configurations (rooms in different places, different subsystems), and since going through the game is so random each time (different crews, different weapons, different subsystems, different buying order), although each game will take less then a single hour, there is huge replayability, even using the same ship over and over.
I have played like twenty hours already, and have only went in depth in two ships (and one class each of those ship), out of all the ones available. I know that there is a very long time left for me to play in this game before it loses all replayability, and even then a new expansion (and I think they will have an expansion) could add A LOT to the game (easily dozens of hours more with pretty minimal effort (eg. adding a few new ships, adding another race or two, adding a longer possible campaign mode)).