I’m a newcomer to IF. I just discovered it through Porpentine’s games a few months ago. So my opinion’s not too valuable about what games have done in the past or how player expectations have evolved, but I can chime in as a newcomer and say what appeals to me from what I’ve seen.
I mainly want to chime in after reading the comments here about developing more complex worlds and NPCs as opposed to simplifying them. The parser is such a wide-open format – when you load up a game, you can type anything – that I suppose making it receptive to more varied input is a natural goal for authors. But the games I’ve enjoyed most have pared-down actions, which you learn pretty soon into play, so that you don’t have to worry about tinkering around. You know your capabilities; you have an environment; you employ those capabilities.
I’ve never yet had an “aha” moment where I realized I had to do some new action to solve a puzzle. Normally when that happens, it produces an anticlimax because I’ve been fiddling around and have failed a few times already. I just want to get on with it.
But I do enjoy complexity in games, and I like talking to NPCs. Weird City Interloper was great for me for this reason, because your actions are super limited, and you know it, but that doesn’t stop the game from having a very colorful and diverse cast. Maybe not the fairest example, since the game is built explicitly around NPC dialogue, but I think it’s a good example to show how you can have a complex story and interesting NPCs while having the most (appealingly (to me)) bare-bones implementation.
So the answer in my view is not to avoid complex NPCs, but rather to figure out a system where a player has limited actions with wide-ranging applications. Even the basic commands are often too finicky for my tastes. I want “examine/search” to be the same. I want “talk to/tell about/ask about” to be bundled together. I want “push/pull” to be fused into something like “move.” A command like “engage” could even combine “push/press/pull/turn,” etc. But the main thing would be to spell this out when the game starts so that the player knows what tools they have to use. I imagine it would also free up the author, since the author wouldn’t have to worry about implementing various random things the player might attempt.
When it comes to unimplemented objects, I do find those “You can’t see that” responses annoying, but that’s easy enough to fix by writing a more flexible error message. Something like “Your attention would be better directed elsewhere.” I’m actually a little surprised that the default message isn’t already something like that.
Anyhow, that’s just one more opinion.