Besides the refinery, cargo and commercial stations, what can we expect as far as other kinds of stations or orbital structures?

We plan to have quite a few. As mentioned, refinery, rest stops, cargo. We will potentially have manufacturing plants, security outposts, pirate hideouts, everything that will fit in the universe. Really anything that has a gameplay element is a possibility to be turned into the function of a space station somewhere as well. So you won't just see a universe of rest stops. That's not really the intention.