These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Designated Hero: Carl from The 11th Hour doesn't exactly make the best first impression in the intro. His response when Robin says their relationship makes it look like she's slept her way into her position is "Well, didn't you?" Followed by a crude joke about her 'many talents' and telling her that he hopes she's the next one to disappear while investigating the Stauf Manor. Sure, he goes to try and help her, but jeez.
Ear Worm: "Dolls Of Doom", while fitting appropriately in the first game for the reveal of the dolls that hold children's spirits, it's horribly overused in the 11th Hour. Not only is it the credits theme AND the intro, it also plays whenever you consult the Game Book - and you will, a LOT.
Most Annoying Sound: Ego's most spoken phrases, "I'm going to have to start again" and "Which way should I go now?". The latter is only used for a few puzzles, though, and the 11th hour replaces it with a pulsating eyeball icon. It also doesn't help that when you reset any puzzle in the first game, all the spoken dialogue is repeated.
Narm/Narm Charm: Thanks to the voice-acting, this wasn't nearly as terrifying as it could have been.
Nightmare Fuel: Stauf. Everything having to do with Stauf, amongst other things.
Padding: Oh, so very much in 11th Hour. The entire game is essentially one Fetch Quest after another, split up by puzzles.
Polished Port: The newly-released iOS versions of 7th Guest eliminate the most annoying part of the original game by speeding up the transitions immensely, cutting down on the waiting significantly. On the other hand, some hotspots are a bit too small for the tiny iPhone screen, and some puzzles have been ommitted entirely — including the Microscope puzzle.
Porting Disaster: The CD-i version — and yes, such a thing did exist. On the one hand, the transition scenes are much smoother and the sound quality is excellent; on the other hand, the joystick interface is very clumsy, some scenes are missing their background music, and the loading times are both irritatingly common and inexcusably long (with one puzzle taking almost twenty minutes to solve with the lowest number of moves). Some of the puzzles are also missing, including the infamous soup can puzzle, which may push the port into Porting Distillation territory for some.
That One Puzzle: The Microscope Puzzle, which is a game of Ataxx against the AI — whose intelligence, unfortunately, is based on the computer's processor being able to figure out the best possible set of moves in a set amount of time. It was possible to beat back in the days of Windows 3.1, but now it's borderline impossible without locking the available processor speed using an emulator such as DOSBOX.
11th Hour has the Beehive Puzzle, which is pretty much the same thing, only with a hexagonal board.
11th Hour's concluding game of Pente counts. In order to see all three endings, you need to beat the game three separate times. The first time around, the player gets the first move. On the second playthrough, Stauf gets the first move (which is a hefty advantage all on its own). For the third go-round, Stauf gets the first move and gets to look at least five moves ahead.