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.
Ensemble Darkhorse: Ottoborg, he only appears in game in the Hall of Records and as a picture in Willie's room, but he's the most popular of the seven kings. Even Hoborg who created the Neverhood itself isn't as popular as Ottoborg is.
Genius Bonus: Several of the stories in the Hall of Records get much funnier if you're familiar with the esotericisms being parodied (like Gnosticism).
There are some jokes (like Willie's "Absalom" crack) that only make sense if you've read the Bible.
Not to mention a very large percentage of the fandom is from Poland. There wasn't even a Polish translation of the game. There was a Russian translation, but there's only a few fans from Russia, interestingly.