Let’s start by thinking about the reasons anyone would want to visit the moon:
1) It’s the moon!
2) Low-gravity sex – and, uh, other activities
Number 1 means that when someone looks out the window, they expect to see pristine lunar landscape, not the tracks left behind by the construction equipment. Brian’s offer to head up the lunarscaping crew notwithstanding, any marring of the terrain (lunain?) will be permanent.
So how does one create a structure without touching the surrounding land? My thought is to learn from the mushroom – pop up from underground overnight.
Man, I wish I had a napkin scanner now.
Anyway, the idea is to start by going underground. For health and safety you want most of the complex beneath a layer of rock anyway. Way deep you bury your reactor; it’s going to take a lot of energy to build the place. Then above that you put the living areas.
Here’s where it gets good. From a shaft in the ground you extend a giant umbrella, open it. Its reach extends far past all the destruction caused while digging the shaft. Set it down gently. Beyond that plastic bubble the moon is untouched, looking exactly the way it did when dudes were spitting painting onto cave walls. Good viewing!
The actual umbrella will probably have more than one layer, and some sort of optically-neutral gel between the layers to plug micrometeor hits well enough until a better patch can be applied. But I’ll leave those details to the engineers.
There would, of course, be a location where guests arrive and depart; that will likely not be as pretty. It would be out of sight of the main city, connected by tunnel or – Ooo! – by a graceful elevated rail to give spectacular views as guests arrive. Building that without ruining the surrounding countryside would be tricky, but probably worth it. In the low gravity you could build something that really defied imagination, something that our common sense would say must fall down. Definitely worth the effort.
As far as point 2 above, Brian V. already has dibs on the astro-jump concession.