I think it is sad that most not-main NPCs only have certain roles and mostly short stories, after that they are like forgotten, sometimes we go back to them to trade something and that's it.
For example Esmeralda in DOS: we made the investigation, she was in jail or not, but after resolving Jake's murder she didn't have any more role. And this is true for almost all characters in DOS. Sooner or later they are just empty.
Similarly if we discovered and plundered a location, there is no more reason to go back, even if it was a nicely designed, beautiful place.
Well, sometimes I'd love to see that after many gaming hours we have to go back and speak with an old NPC about something totally new and different from earlier topics, they could move more also, it could be fun to go here and there on the map just to find a moving patrol or traveling people, whatever.
Also it would be cool to find something, a treasure map or another reason for going back to an old location and find something new. Or we have to pick up something from a long fallen foe, similar.
I know, some of these were in DOS in a form or in another, for example the treasure maps, but still..
I know some of this ideas could be hard to implement, but I'd love to go back to old NPCs and have new dialogues with them about totally different topics. That could be much more depth for them.
Recycling is not the exact word for this, but sounds ok.
What do you think?