What if you added a shit-ton of planters and skylights/lights in the huge main hallways (assuming skylights aren’t there already, which they are in a lot of cases), and put windows inward toward your year-round community gardens? The inward-facing walls tend to be glass, so would need to be replaced anyway, and those hallways and congregation spaces are more than wide enough for abundant edible greenery if there aren’t sales kiosks and junk everywhere. You could make a really inviting view entirely indoors.

Retrofitting the plumbing might be a bit of a problem unless you made everything high efficiency, and just built up the floor a bit, which I think could be a fairly minimal expense by going down the main hallways to existing facilities, with shared plumbing between two units/stores like a duplex. (those cement floors suck anyway, so you’d want it built up at least in the units). That makes it easily accessible for fixing. Or a lot of places have back hallways, you could run exposed plumbing through those and run directly into each unit.

Keep some of the kitchens in the food court running, open some markets/maker spaces or create hangout/childcare options in the big shops that can’t be converted to housing, and you can employ people and give them access to quality resources with whatever access issues they may have. Plus then you could rip out 90% of the parking lot and plant trees or build more housing or something. That sounds pretty economically sound to me, just not up front. And not profitable for anyone who would spend on it.