Window frame colour.
Window glass colour.
Brightness of lit windows.
0 = day, 1 = night: how much lit windows glow. Drive it from a day/night cycle.
Size of the procedural wall and roof patterns (bricks, planks, tiles): 1 = real-world size.
Roof colours per material; flat roofs use concrete (baked into geometry).
± brightness jitter per building, 0..1 (baked into geometry).
Wall colours per material; each building picks one (baked into geometry).
Colour of lit windows (#rrggbb).
Window grid per building style.
Facade and roof look. Everything except the palettes is a shader uniform (instant to change).