I'm new here, (first post), and wasn't sure where to post this... but I'm confused about why it's so hard to create a docking mod. It only needs 2 parts- a cone and an active piece that goes into the middle of the cone. All you'd then have to do is launch a sort of booster mission into orbit, have it dock in back of a lander/return vehicle, apply thrust, and then you're going (perhaps not turning, unless you add a part that can go around the cone and its housing area). When you run out of fuel, have the kerbenaut in back do an eva and walk to the front vehicle, get in the vacated seat, and disengage from the docked area, flying the next vehicle. This way, you don't even need to have moving parts. In addition, even if you don't want to do all the work to create a cone and active piece to dock with, you could just hollow out a structural fuselage, and add a smaller, pencil-shaped piece just a little smaller than the hollow area, and try to dock (this would be harder to dock with than a cone, however). This came to mind when thinking about the movie, apollo 13, where they use a cone-shaped docking system- a very simple system, in my opinion.