Tacked-on campaigns aside, in the X series you're a pilot with a ship plonked somewhere in a vast network of gate-linked star systems, aspiring to wealth, power, reputation, empire, chocolate-- whatever you want. You can pilot anything and go anywhere, and nobody will refer to you as the "Argon Skunk" unless you tell them to.
In X-Rebirth, you're locked into an M3+ fighter with a fixed co-pilot. You and she both have terrible voice actors. Your ship name is locked to "Argon Skunk", and it will be referred to by this name EVEN in free play mode. Gone is most of the X universe; Argon Prime is bigger than you'll remember, but the map is still miniscule relative to other X games.
Yes. "What the hell were they THINKING?!". That's what I thought too.
What were they thinking confining you to only one dreadful looking ship with an awful mandatory name, just for the sake of realizing a handful of rubbish looking interiors? What were they thinking cutting out most of the rest of the X universe? What were they thinking abandoning all the AI surgery performed by the community for X3:TC and AP, and releasing broken trash again? What were they thinking simplifying trade to this extent? What were they thinking abolishing autopilot and time dilation- and with them, the freedom to just watch the universe play out?
If you've been a fan of the series up to now, you'll be asking `what were they thinking` over and over, sometimes with a sigh and sometimes with a scream, always with your face in at least one palm.
You might also wonder why every single bar in Argon Prime is a strip joint advertised by red neon banners featuring nude women with their backsides turned? Why gates were replaced with Freelancer-but-uglier space lanes? Why at the end of the space lanes all traffic just disappears?
Let's dispel those unanswerable questions with a complete list of the positives.
It's no Star Citizen, but it looks okay in space. Not great, but not bad. Some of the weapons' effects are nice, and capital ship explosions are no longer two dimensional fireballs that don't even occlude the ship model blinking out of existence.
So there's that.
Rebirth is a space lemon if you're new to the series and an unmitigated disaster if you loved anything between X2: The Threat and X3: Albion Prelude.
Avoid this game, and don't hope for eventual rescue from the modders this time either: the X games have always required vast community support, first to make them playable (X3:TC without M.A.R.S scripts plus gigabytes of other stuff? You're going to have a bad time), and then to make them great... But nothing short of a total conversion will suffice to make Rebirth better than a complete debacle.
I don't see anyone loving it enough to do that sort of work.