If I could make a suggestion about the physics modeling. As the rocket get built, could the physics be combined for the craft as a while instead of individually. Understandably this would require a rewriting of some of the physics coding. But as we all know, when the part counts get higher, it takes much longer to process, and drops the frame rates horribly. So instead of modeling 200 parts, the craft would be modeled as 1 part, and as the stages are released, the weight, density, and aerodynamics would change. Docking ports would be an exception though. Since a docking port connected to a docking port isn't a structural connection, it would act as quote breaking point in the part count. just as a suggestion though