You know, something that would most likely be MASSIVELY code intensive but incredibly fun and immersive along with being a potential mid to late game goal would be establishing communication networks again in some way. Maybe have radio towers be able to actually send out signals and have people respond and talk to you over your radio would make companion gathering for camps better (have not dabbled in radio towers or camps much so maybe you can already do something similar.)
Set up enough towers or just get lucky, and automated music stations might start up, either thanks to bored survivors elsewhere or they were just too weak at the start. This could provide massive morale boosts when compared to MP3s cause you could actually tune your radio.
Or set up makeshift internet servers and boosters, along with a few random hotspots, and you could bring back a semblance of connection via internet. Maybe you get it as a quest from NPCS at the shelter, maybe you get approached by a vestige of the government looking to reestablish comms after x days cause they have been watching you and you look more capable than the rest. I don’t know the deeper parts of lore for CDDA.
Also, this makes could make quests much easier to do? Give a radio to someone who either asks you to get something or do something assuming you restored the tower’s power (and now it can actually signal boost other signals), do that action or get that item, and then you can radio to the quest giver to move to a tile. They will then “move” (teleport) to that tile after x days! No longer do you have to backtrack all the way back to somewhere just give a guy an inhaler of the nearest pharmacy was in the next town over.