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.
YMMV: Legend of the Seeker
Author's Saving Throw: When Nicci originally appeared, she didn't look at all like her book incarnation and did not wear black. Then she was resurrected in a blonde body. Then she became Badass. Then, for the season finale, she put on a black dress.
Darken Rahl himself. Commits mass infanticide, murders for kicks and for ink, horribly tortures people to gain magical powers, etc. He has his own sister violently beaten, lies to her so she will betray her other brother and bring him the tools to take free will from every living thing in the world, he also unleashes a plague on his own people (killing hundreds of them including a meek looking boy we are shown) for the sole reason of trying to turn people against Richard, and when all of this fails to win him victory he ''kills a kitten with his BARE HANDS'' . Bonus points come from that all of the above happens in one episode.
Princess Violet and her mother as well. Queen Melina is so horrible, that when Rahl kills her, you feel like it is his Pet the Dog!
Arguably they were even worse in the book.
Engaging Chevrons: When Kahlan uses her Mind Control "Confession" power on a person the first time, the clouds part, the sky darkens, thunder rumbles, her eyes go black, and she passes out for nearly a minute. Averted, in that the production quickly tones it down for subsequent uses. By the second season, she barely breaks her stride.
In the episode "Home," Rahl, as part of a spell inflicting a Lotus-Eater Machine on Richard, ends up roleplaying as an old girlfriend of Richard's.
And apparently the Keeper and the Creator were once lovers. Part of the reason he wants to end all life is he's jealous of the affection she shows to them. And in "Creator", he desperately tries to have her avatar dragged into the Underworld to be with her again.
There's also quite a bit when Nicci is forcing Richard to lead her to the Stone of Tears.
Growing the Beard: The first two episodes are rather rushed, basically cramming the first third of the original book into an hour and a half of screen time. The rest of the episodes have a more relaxed pace, and are a substantial improvement. In the premiere of the second season, this trope took a literal approach as well (Richard actually grew a beard.)
The second season marks a noticeable improvement. The series becomes darker and there is much more suffering for both the main cast and the people around them. The D'Haran army, now leaderless, has turned to pillaging and terrorizing villages and towns, each commander fashioning himself into a warlord. There is also some (very welcomed) character development, especially with regards to Richard: he no longer carries the Idiot Ball all the time and at several points displays downright tactical genius (tracking the movements of invisible wizard-monsters by the tracks they leave in the mud; the way he both had the Sister of Dark captured AND got out of the Sisters of Light monastery). The addition of Cara to the main cast has also improved the series, since she is not only eye candy but has an interesting character development arc of her own.
After several teasing shots of the Mord-Sith giving each other sponge baths, the two in question kiss in a later scene. Can also qualify as Fanservice. Cara's reaction to Triana's death in the Season One finale might suggest more to that relationship in the show, especially in light of "Eternity" and Cara's canon relationship with Dahlia. Let's just say the Sisters of the Agiel are all really close "friends".
Tear Jerker: The end of the first part of the second season finale. We've gotten to know Cara as a tough, no nonsense Mord-Sith who had nearly all her kindness and compassion beaten out of her. Then we're introduced to a Cara who got to live the peaceful life of a schoolteacher, and raising two young children with the man of her dreams... seconds before Zedd needs to turn back time and give her back the life she used to have as a Mord-Sith. Seeing Cara, bound, confused, panicking, and pleading for the sake of her children is... hard to watch.
The Woobie: Among the first things which happens to Jennsen Rahl are getting kidnapped and then watching her mother die. It tends to get worse from there, and in the first half of the Season Two finale, in an alternate timeline, she's kidnapped by Sisters of the Dark, who drain her blood and leave her to bleed slowly to death.
They Changed It, Now It Sucks: While there are legitimate grievances to be had, some of the earliest complaints were along the lines of "They changed Rahl's hair color! SAM RAIMI MUST DIE!"
They Wasted a Perfectly Good Plot: The last episode features two stories that connect. One of Richard and Cara in the future trying to return home, the other is an alternate timeline where Kahlan marries Rahl so she can give birth to an heir that will help Richard return home. The last episode felt like it crammed two episodes together. Both sides might have worked better if they were their own episodes. Especially Kahlan's marriage to Darken Rahl, which seems to be popular with fanfiction writers.
Too Cool to Live: Care bore Darken Rahl a son, whom he had killed at birth. Just let all of that sink in for a moment. It may be a nod to a scene in the books, where Cara notes that Darken Rahl had taken her to his bed several times, but she was lucky enough not to get pregnant (in the books he tended to do that to the mothers as well, and it happened to a number of her friends).