Think of a cross between Kerbal Space Program and Harpoon.
Ultra-realistic largely turn based space combat game. If matching orbits with some punk and launching some killer drones, shunting them into a flyby trajectory to railgun your opponent as they bez past at 1000 m/s is your bag, then this game may just be for you.
It reminds me very much of the ship to ship combat in The Expanse. Launch 50 nukes and wait an hour or so IC time before they hit. Rather like Harpoon, missiles are essentially puzzles, set pieces which you have to 'solve'.
A lot of care has been spent on making everything scientifically accurate, there are a lot of files to read which often have a link to whichever RL science symposium or whatever they are derived from!
The good : awesome concept, well executed. Reasonable tools are provided to handle the complexities too, it's far easier to plot an orbital rendezvous in this than it is in KSP, so fear not, though KSP players will be instantly familiar with how this works, and also with the controls to an extent.
The bad : its 150kb to download which says it all. As much eye candy as Harpoon had, ie none whatsoever. The campaign isn't very long. There is a sandbox, which lets you make your own space battleships and send them in against each other. There is no multiplayer.
The indifferent : its turn based (sort of, it's a sort of freeze time thing really) and unlike KSP you don't directly control your ships. Maybe this appeals. Maybe it doesn't. At 19 British beans I think it a tad overpriced as well. Stick it on the wishlist, wait for the sale.http://store.steampowered.com/app/476530/