My thought, and I don't know how practical it is, is that I would like clerestory windows of glass block. In other words, a row of glass block near the ceiling such that you get natural light without compromising your privacy in a city location.
I've lived in two old buildings in a downtown area. There's no view and if there's another tall building nearby, you never open the shades or curtains because the view sucks and now people can see into your unit.
In a small space, windows break up the wall and interfere with furniture placement. If there's no view, they are all downside, no upside.
You probably need one proper window somewhere as a potential emergency exit, but windows should provide real value, either natural light or ventilation, and I'm finding they mostly don't in these old buildings in a downtown area.
Glass block clerestory windows would be an improvement over what I have currently.
Ideally, the units should be comfortably habitable with NO heat or electricity. Adding appliances to cook, electricity to power mobile phones and other devices, etc should ADD functionality. But I would like them to be comfortable places to sleep and exist without having to necessarily heat them, cool them, etc using powered devices.
Ventilation should be designed in without needing appliances for it. This can be done with building design.
If the person can't afford electricity or power outages are a chronic problem, the unit should remain a viable habitation. Daylighting of the unit is an essential part of that plan.