So, sorry if this was mentioned before, but I discovered* that you can offset the root part of a craft with the offset tool. This doesn't seem like a useful thing at first, but it lets you overcome those annoying times when the camera just doesn't let you move the rocket to where you want to inside the VAB. Or...you can do this: Yes, this is a craft offset almost 15 kilometers away from the KSC, which is pretty far away[citation needed]. It's amazing, and offers tons of possibilities (like starting a boat, barge, etc. in the water). The way you do this is by selecting the offset tool (obviously), clicking on the root part, then "grabbing" an axis of the tool and moving the mouse up, perpendicular to where the axis is pointing. Done correctly, it should let you offset whatever craft a ridiculous distance away (it clips through the VAB or SPH walls). I don't know if it allows you to start a craft in the air, but theoretically it should be possible. TL;DR: You can offset a craft's root part to move it really far away, holmes. *I discovered this quite a while ago, but I was too shy to post it until now