I want to imagine myself docking to a gigantic space station, its about 20,000 km around the edge, shaped like a sphere, and it "rotates" at about one-one-hundredth of an RPM (Revolution per minute). There is a single "docking station" like situation 2, on one of the poles, called "McMurdo bay, Antarctica". Do people at McMurdo feel dizzy? No. They can't even tell they are "rotating". If I were landing a spaceship there would I feel dizzy? No. Even though at the edge of this giant space ship, people are "travelling" about 1670 km/hour. This space ship is the Earth and to everyone on it's surface, it appears still.
In other words, the idea of "rotation" is like the idea of "movement" - in space, at speeds much slower than the speed of light, it is all basically relative, and we only feel acceleration, not any kind of "absolute speed". Go back to Einstein's thought experiment - if you were inside an rocket ship accelerating so that your feet touched the floor at a nice comfortable earth-simulated-gravity of 1g, could you tell whether it was from gravity or from the rocket engine being turned on? assuming you ignore things like seeing the walls, etc? In other words, if you are at a stop light, and you see another car roll backwards out your window, without being able to see the background for some reason, then does your brain sometimes wonder if they really are rolling backwards or are you rolling forwards? If you are on a train going 245 MPH and you drop a ball out the window, did you throw a ball at 245 mph? No, you dropped it at 0mph, its only relative to the ground that its going 245 mph.
What I'm challenging is the idea that people will be dizzy from rotating at a constant rotational speed any more than astronauts can "feel" they are going a linear constant speed of 25,000mph. If a cosmonaut, astronaut, or taikonaut has no windows to see the distant stars, i do not believe they would even be able to tell that they were rotating at all, given a low enough rotation speed. We only really feel "acceleration", or, a quick change in speed, we dont feel the absolute speed. That is true of linear speed, and I believe it would also be true of rotational speed. Given low enough RPMs.
Now, there is a problem if you were rotating too fast... but how fast? A quick google search shows that the RPM for a space station thats rotating to simulate earth gravity will be somewhere around 1 to 3 RPMs, depending on the radius of the station. Now how fast is 1 RPM, for a human mind?
Stand in the middle of your floor. Now get a stop watch and set it for one minute. Now, turn around so that you will make a complete circle in one minute. That is one RPM. Did you get dizzy? Could your brain even tell you were rotating? Close your eyes and do it. Could you tell you were rotating at all?
Its the same principle almost that Virtual Reality uses. If you close your eyes and walk in a straight line, most of the time you wont be able to do it, because your brain cant even tell what a straight line motion is. It doesnt care that much. Thats how VR can simulate walking on a path even though you are in a tiny room - it tricks you into walking in circles without your brain even knowing, because it shows you walking a relatively straight path using distorted optics. Our brains are not that sensitive to motion as we like to think.
In other words, In my opinion, option 2 is not really a problem. Other than the problem of getting two ships to spin at a very close rate of spin. If we watch a movie like Interstellar this seems quite dramatic - but only because Chris Nolan's team was showing us the background stars, planet, etc, pumped the music up, had dramatic character moments at the same time.
In reality, imagine docking against some huge rotating ship. At some distance the view screen will only show the ship. No background. Now assuming RPM is low enough, you wont even feel the rotation, just like you cant feel the rotation in your room turning around at 1 RPM. It will essentially be just like a normal docking procedure against a 'stationary' space station, except that you have to "correct" your "rotation"... which is what we do already every time Soyuz docks with the ISS. It has to make itself steady in regards to the other ship, and it has roll thrusters to accomplish that, should there be some inadvertent roll for some reason.
As you get close, and the station looms large in your view, the rotation itself becomes an illusion - you and the station are actually standing still, it is the rest of the universe that is spinning. But since you cant see that universe, you don't even notice.
This is like the illusion we have on Earth every day. I do not feel myself rotating on an axis at 1600 km/h. I see the moon and stars spinning around me if I look up and wait long enough. I do not feel myself rotating around though. I feel still. The ground feels still. The roads and buildings and mountains feel still and immovable to me. I do not feel myself rotating around the Sun either. Nor do I feel the rotation of our spiral arm aroundst the center of our Galaxy, nor do I feel the movement of our galaxy cluster in relation to others. It is relative.
And so in my humble opinion, the realistic option is number 2.
The other options will introduce unbalanced mass to the station and cause wobble, which is a much much bigger problem. As for stationary piece of the station, that involves some kind of super complicated air-tight slip ring system to mate the stationary portion to the main portion, again more problems.
And fuel required to rotate is very small. Remember essentially there's no friction in space. What if the ship has run out of fuel or thrusters are inoperable? Then either the people can get out and spacewalk or the station can send a rescue pod, like a little tugboat, that can attach to the ship and force it to rotate
Once it is rotating, there will be almost zero additional propulsion needed, it will keep spinning by itself. Just like the planets spin - even though they dont have rockets strapped to them.
Now ... I realize there is a big question here. How can people feel 1g on the space station if it's rotating, but they feel nothing at the center? What's the point of all the rotation if nobody can feel anything from it?
That goes to the crucial factor about artificial gravity, which perhaps we can alternately call artificial simulated gravitational acceleration through centripetal motion. The artificial gravity here is dependent, entirely, on the distance one is from the center of the object rotating. Just like on a merry go round, or on a ride at a fair, or even like an ice skater - when her hands are tucked close to her body, there is not much feeling on them, but when she lets them branch out as she widens her arms to a wide pose, she can feel her hands getting "heavier". In other words, at the center of the rotation, the artificial gravity is essentially zero. Only at the edge of the ship is there any feeling of artificial gravity - and that is only because your body is accelerated by being in contact with the ship, as you make your way out to the ring. You will most definitely feel the weight coming on you as you travel through the Jeffries Tubes or whatever from the central docking bay to the outer ring where everyone lives. But that does not mean there will be artifical gravity at the center of the station.
Of course until someone actually builds it.... I wouldnt say im 100% sure!!! But thanks for reading if you made it through all this.