Gothic 1 and 2 had that amount of NPC interactivity too.I would love to see Mafia II levels of interaction with the world around us.
Interacting with items everywhere, using common services (any vendor or service, not just the typical RPG equipment vendors), being able to interact with doors/cars in various ways (open/close, kick in, smash down, pick lock, shoot out lock, etc).
And we should be able to talk to EVERYONE. Not just specific NPC's.
Take a look at a classic like TES: Daggerfall. You could talk to pretty much any NPC on the street. Not just special ones. Any random person you could walk up to and ask for directions (they would mark things on the map), ask about where to find work, ask about local history and politics. We need that kind of option in this. Naturally not everyone needs to have a huge list of things to say, but being able to ask any random NPC on the street basic questions would be great, and make sense. And of course, different people would have different personalities. Some would be happy to chat, some won't talk to strangers, others will be violent or insulting. Give us random people that we can interact with. Having the swarm of faceless and speechless NPC's is honestly just stupid. It really doesn't fit in any game.
Most games just have non-important NPC's spout off some random comments, but it makes no sense why we can't just walk up to a guard or merchant or just person on the sidewalk and ask how to find X or what's going on in the city.
Such great games.;D