Kerbal is a lot of fun, if you can get into that sort of thing.
Breathedge I found confusing and lame, it's the same conceot as subnautica if you played that just worse in every manner.
X4, wanted to buy into that for ages, last I played was X3 many many years ago. What I remember is the supply demand delivery breaks a lot and the universe just died in a couple days of gameplay. Also combat and flight in general is really atrocious.
If you're into strategy games, Master of Orion (remake by the same ppl that make world of tanks) is a rather decent one. I enjoyed a couple of rounds if that and I'm not that into this genre anymore.
If you want an annoyance, I mean rogue lite, Everspace (2?) is decent. I played 1, it was... Okay I guess. Just don't expect any sort of depth from any of it.
Stellar is a classic for strategy, I never played it though, only seen streams. There are lots of great themed mods (SW, Stargate, Star Trek, Wing Commander...)
Last time I played something like this was imperium Galactica 2. That was like 20 years ago.
There's also no man's lie and Ed but you played that to death in the first hour or two just like I did...
Ehh, enough of the modern trash. It's all just a pale imitation of what was actually good once.
If you want something that's very much like the old wing commanders, there is Darkest Dawn. It's a free mod of Freespace 2, but it's fully standalone, just a 4 gig or less dl.
BTW, have you played Freespace 1 and 2? If you haven't, why are you still here? Do it NOW!
Its the very last of the proper real "space Sims" we had. I will never ever forget the moment in fs2 spy mission flying a captured fighter, and the moment I it loaded in, the Ms sidewinder FFB stick in my hand rumbled like all hell and my wingman was shouting Dive dive dive!! as a... Nah, don't wanna spoil it fully. It's proper awesomeness, not just for it's time!
. I'm pretty sure you can aquire both of them for free by this point, they are abandonware with the source code freely available and the OG FS1 campaign was ported over to to the fs2 engine ages ago, so you can play both in one game. It's rather good, to say the least. It might be a bit of a hassle to set up on a modern machine, but it's so much worth it.
Edit : horrendous typ's, fuck autocucumber on my phone..