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.
Though this seems to be a "Harry Potter" type of scenario, that being a naturally born hero, no matter how abused he was as a child, his natural good nature overpowers everything else.
Canon Discontinuity: Mask of Eternity has not been put on any of the compelation CDs, nor written into the Novelization-style game guides. Though on GOG it is bundled with Kings Quest 7, in turn forcing you to buy it if you want the latter.
Even Better Sequel / Growing the Beard: The series' gameplay, graphics, logic and overall quality tended to improve as the series progressed, with KQ VI generally being regarded as the highest point of the franchise. However, KQ VII had a mixed reception, though positive in general, and KQ VIII was a huge letdown that ruined the series.
Fanon: In the AGD remake, a hidden letter (search Manannan's desk four times) from Lolotte to Manannan states that her "Sister" once had a crush on Manannan before he grew out his beard. Her sister is stated to me Malicia as they're both fairies. Not to mention Both had a connection to Edgar, and Malicia may have even aided Lolotte in kidnapping him the letter also states that Hagatha is Manannan and Mordack's sister. While ALSO confirming Lolotte and Hagatha as part of the Black Cloak Society. Though this game had Approval of God it's still nowhere near Word of God.
Fanon Discontinuity: Mask of Eternity was not well-received by the fanbase, to the point where it's debatably In Name Only. Even the old-school Sierra staffers distance themselves from it.
Though bizarrely, despite being reviled by most of the fanbase, especially the hardcore fans. Fan games such as KQ 2 AGD, and "The Silver Lining" still state it as canon.
Fridge Brilliance: To explain the whole Fantasy Kitchen Sink scenario. Think about it? Once the books in our world are finished, the characters have to go somewhere. Perhaps Daventry is a purgatory of sorts, for literature characters whose stories have ended, with no writer to continue them, they end up here? note I would not count if a new writer eventually takes over, as each character is bound to the writer who created him/her/it. While the "new writers" may have the same characters, that would in turn create a second incarnation who is similar. But not exactly the same, as different writers, no matter how accurate they try to be, can never truly duplicate the original writer
Narm: "A POIsonous snaaaake! A POIsonous snaaaake!"
WTH, Casting Agency?: Lampshaded in a Let's Play of King's Quest V (the CD-ROM version of the game was voiced by Sierra employees, with varying degrees of success. Sierra learned their lesson, and pioneered the concept of Hollywood actors voicing computer games.)
That being said, they still kept developer Josh Mandel as Graham for VI (since he's usually considered the one employee who actually did a pretty good job with his VA) and Mandel has been gracious enough to lend his voice to the fan-done remakes.