re: ISS as a space dry dock?
"Could the ISS even be converted into some kind of space dry dock for building ships to launch to other points in the Sol system?"
Rather propellant inefficient to launch them to the ISS inclination to do so - both in terms of mass going up the hill to ISS, and lunar / martian trajectory injection. Consider the parking orbits of the SIV-B boosters or, say, MRO.
Doug