The shielded windows of in-surface structures which use mirrors and bent optical paths to thwart radiation, will be a cumbersome relic of pioneer beachhead days, still used where Lunans must live in the regolith blanket surface rather than in provident subsurface voids. Tube structure windows may be characteristically convex, curved in to the pressurized interior, so as to put the panes under compression. Glass and concrete are stronger under compression than under tension. Nor will in-tube windows need sacrificial panes. So tubers may share with topside moles the practice of placing plants in front of windows as a psychological filter.
Many architectures are possible.
The design type might be called the Yurt or Hogan after the Mongolian and Navaho home shapes it resembles. A dedicated shaft of directed sunshine on such a dome would surely help set the mood. The early lava tube settlement will not be an assembly of individually pressurized buildings, but rather, like the in-surface burrowings, a maze of structures conjoined by pressurized walkways, streets, alleys, and parkways. In the netherspaces, thoroughfare cylinders can be generously paned with convex windows to flood their interiors with ambient reflected and diffused sunshine and views. Along with solar access for reflection off coated upper tube surfaces, there can be some sunshine ports that direct intense pools of light downward, say on the convex-paned lunar geodesic domed park squares.