Grandia 2 had these bits where you did nothing but talked to NPCs and it got really annoying because they wouldn't fucking shut up and the writing was bad. I stopped when I got to some town that was like, dying because nobody could eat, and you have to get involved in this long conversation with the priest, then the mayor, then like, Mareg or something. And that's after a long conversation with some random family. And it's long and non-interactive and involves no choices or decisions from the player.
but almost every graphic adventure has at least one of "those" kinds of puzzles, right?
Yes, and that's why the genre's mostly shit and only exists as a vestigial husk of its early/mid-90s glory days.
I think the issue I have with most of the 90s-era graphical adventure games is that they tended to have this issue where they both tried to be funny and serious at the same time and did a really bad job of it. That was the vibe I got from the little bit of the first Broken Sword game I played. I played The Longest Journey further, but... same issue. And the attempts at jokes were... really, really unfunny there, mostly relying on comedy tropes that had already been exhausted a decade before. Which was annoying because the serious parts actually seemed good but, hey, no, we have to have random lesbians giving lengthy monologues on their sex lives, or idiotic maintenance workers, or a puzzle involving a detective in a bathroom stall because Rated M for Mature CLEARLY means potty humor. The insipid puzzle designs didn't help much either.
Also there's the whole walking clusterfuck known as Roberta Williams. Every game she designed was basically and exercise in figuring how much meth she was on when she came up with it. King's Quest 5 is pretty much the pinnacle of bad puzzle design. Most of the other KQ's weren't much better, with the exception of 6, which was mostly Jane Jensen's doing. I'd have a hard time saying the Space Quest games were much better, although the earlier ones have the excuse of being really early examples of the genre. About the only series to come out of Sierra that I liked was Quest for Glory, which were more RPGish, generally more consistent in tone (They HAD comedy, only it was actually funny and wasn't nearly as distracting), and most of the puzzles in those games had like 30 solutions so even if one of them was really obscure you probably wouldn't get stuck forever.
For the record I don't hate adventure games at all. I just think Sierra was by and large complete trash and that TLJ was really overrated. LucasArts generally put out games I liked. Like, I adore Monkey Island, because those were intended to be funny and generally actually were. And I'm a huge Myst fan and never found the puzzles overly obtuse (Except for the FUCKING GODDAMN FIREFLIES in Uru god fuck that fireflies fucking fuckshit) since they generally were solvable via the scientific method and observation (also only the first game was scant on story content. The rest were this... you know, house of leaves is a pretty good comparison. Especially Uru. Uru was great except for the FUCKING FIREFLIES. It's highly meta-fictional, with this theme about the relation between an author and their work/the reader and the work, or this can even be expanded to work with gaming and not just books, and there's this huge family drama. It's pretty epic).
Also Planescape and Ultima 7 being for all intents and purpose adventure games, despite the RPG elements.
I tend to prefer mechanical and character based puzzles to strictly inventory based ones. The problem with most inventory based graphical adventures is that you have poor feedback. Text adventures actually got around this by giving you a huge arsenal of verbs. In a graphical adventure you tend to have... well, KQ7 is a good example.
At one point you need to tie a rope to a rock. This isn't exactly intuitive for a number of reasons (The end result is that you set up a barricade to trip a jackalope or something). The problem is that KQ7 only had one action -- use. So, using the rope on the rock. What is that supposed to do? Are you throwing the rope at the rock? Smacking the rock with the rope till it cracks open and reveals delicious candy? Lassoing the rock away from some hole? The interface never really makes it clear WHAT the actual result of your intended action will be. Curse of Monkey Island was actually a lot better about this. Despite having a single use command, it'd change the interface text contextually.
Also you tend to need robust fail response. If you try to use X on Y but that wouldn't work, you need to be told WHY that wouldn't work to accomplish what you were trying to do. Again, text adventures were generally better about this for some reason.
If a graphical adventure IS inventory driven, I think it's better if they offer the player a smaller number of items with multiple, changing, and perhaps emergent uses. Like, Zelda and Metroid games (which aren't strictly adventure games but you get the drift). I think Zack and Wicky for the wii was supposed to be like that too.
I think some of the more open-ended -- in terms of solving things. Not in terms of gameworld -- RPGs tend to make better adventure games than adventure games do. Or, really, most games that incorporate adventure game elements. Deus Ex comes to mind, just since I've been playing it recently.
(Additionally in terms of Sierra I actually liked the Shivers games. Shut up).