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.
Sue Ellen was originally meant to be a minor character but eventually ended up as the female lead, thanks to actress Linda Gray's amazing chemistry with Larry Hagman.
Clayton Farlow was originally going to have a fairly minor role as Dusty's father. He ended up marrying Miss Ellie and essentially filled the role of family patriarch (which was accepted by Bobby and Ray, but not at all by JR).
Harris Ryland is definitely becoming one in the new series.
Fan Nickname: "Pambecca" for Pamela Rebecca Barnes in the revived series.
Harsher in Hindsight: J.R.'s sarcastic reference to the "Who Shot J.R.?" storyline in the first season of the rebooted series, "Bullets don't seem to have much of an effect on me, dear," is a lot less funny when watching the season 2 episode "Furious and Fast", where he is shot and killed offscreen at the end of the episode.
Misaimed Marketing: From boots to Bubblegum Cards to a DALLAS: The Television Show Role-Playing Game.
Moral Event Horizon: Cliff might have crossed this when he ordered the detonation of an oil platform knowing full well that his pregnant daughter was on board, which caused her to miscarry. He effectively murdered his own grandchildren.
To add insult to injury, he even attempted to justify it to the bereaved mother, his own daughter, after the fact.
Seasonal Rot: The tenth Season. The eighth (Dream) season and its aftermath was infamous, but it was the eleventh season that really saw a notable decline in writing quality, the loss of key cast members and a turn towards absurd and/or banal plots.
Seinfeld Is Unfunny: Many of the season-ending cliffhangers are still effective, but have lost something since the days when no television series had ever ended a season on any kind of suspenseful, open-ended note.