Okay, good point. I'm stepping outside my area of expertise, but here's my intuition: Radiative cooling and thermal isolation seem to be fairly well understood

Okay, good point. I'm stepping outside my area of expertise, but here's my intuition: Radiative cooling and thermal isolation seem to be fairly well understood. They can also (unlike many, many other parts of the problem) be tested on Earth. Basically, any satellite needs to deal with this stuff, and designers have been dealing with it for a long while. Now, if you add lunar dust to the mix, sure, that's a complicating factor, but I don't see it being as bad as some of the other things I mentioned.