Riven was the first adventure I played. It's my favourite. In that decade it was a great jump into realism. And yes, there are some people you meet during the game, but without dialogs. Dialogs are at the beginning and at the end (get your mission and finish it).
I think it could be interesting to put in more meetings and dialogs. That's real life: speaking to people, isn't it? Most gamers don't like Myst very much, because it is so empty! The gamer feels like being in a horror movie ( me either, it's fateful and strange). All this games have a lot of machine puzzles and alien worlds, but what about a detective story? The first person is the detective and has to ask many persons to find the murderer. Does it work?