I'm an absolute fan of the game, as said in the title.
Now I googled a little games like it, and this looks really curious. "Battlecruiser 3000AD".
Usually it's not that difficult to get various games, but it's usually a story to find something interesting with exciting game play.
There are couple of old games, currently in mind I actually hold Master of Orion 2 which are really grand, and it's really hard to find anything like of either the same age, or newer.
Suggestions appreciated.
P.S:
I often recall when someone posted here Bitcoin surpassing 1$. I was like, uh.. WTF is this shit back then. Oh well. 
https://endless-sky.github.io/
I don't know Masters of Orion, but endless sky is sfun space exploration and combat game regardless. I recommend it.
Ur Quan Masters is amazing and FOSS.
Hah, I in fact played a game of MOO2 yesterday. While researching a few things about it, I came across comparisons to Galactic Civilizations (2). I've never tried it myself though. Personally, though, I prefer MOO1 to MOO2, as it had less of Civilization-style population management.
aaah, MOO1
I still dream that one day I'll find thew time and energy to do a reimplementation through allegro just for the fun of it.
Battlecruiser 3000AD, oh wow, I haven't heard that in many years. It has quite a history as I recall with lots of promises and lots of problems.
Master of Orion 1 & 2 are awesome. Don't touch Master of Orion 3, it is horrible and completely different than the original.
Ur Quan Masters is basically a remake of Star Control 2, under a new name with up to date graphics etc. Great game though. But nothing like Master of Orion.
Should boot up your favourite compile and library, like Allegro and try your hand at programming something like it. I have always wants to do something similar.
I'd suggest Stellaris. I used to play Master of Orion II a lot. I spent 37 hours over the first weekend I bought Stellaris playing it 
I used to play Master of Orion II a lot.
Same here. Used to play it multiplayer quite a bit. The multiplayer code was buggy at times, but when you got it to work, it was a blast.
I've never played MoO so I don't know how it compares, but Endless Space 2 is free to play this weekend on Steam (http://store.steampowered.com/app/392110/). I've been enjoying it a lot, it's a big improvement over the first game, although the combat is still lacking. The game has a lot of depth. I'm specially impressed about the political system.
There's also the new Master of Orion (http://store.steampowered.com/app/392110/), but I can't tell you much about it, other than it has high production quality.
Ur Quan Masters has consumed me, literally. It's grand, & great. Thanks Chris!
You're welcome! It consumed my life till I finished it!