First of all, I would like to admit to being a teen, and also admit that The Witcher 3 is the first Witcher game I have played, on account of my relatively young age.
1. The concept of evil
You spend three paragraphs emphasising this point. I would advise that you cut it down to zero because it makes no sense.
"The villains are uglier than the heroes."
Well, this is true. Geralt is arguably the only really attractive male in the main game, with the possible exception of Roche, Avallac'h and at a stretch, Lambert. In the DLCs, Olgierd von Everec is quite attractive, but I think Hearts of Stone was released after this comment. There aren't many female villains in the game at all. Of course, Triss, Yennefer, Ciri, and Lil Bleater are all very attractive too.
But it is ridiculous to argue that Radovid is less attractive than Emhyr. Emhyr is old, aged with wrinkled, darkened eyes. His face lacks structure and his hair looks greasy and unpleasant. On the other hand, Radovid has a good facial structure, and his lack of hair is not as displeasing as Emhyr's hair. You mention a facial asymmetry, but I never noticed one.
The main reason your argument makes so little sense is that almost EVERY male character, and many females, in The Witcher 3 looks shit. All of them have puckered, dirty faces and look thoroughly disgusting. All of them look like the Nilfgaardian ambassador in the first chapter. That does not imply that they are villainous at all. It is just that CDPR typically put more detail into making the women attractive than the men.
The Wild Hunt, while not handsome as such, are not ugly either. They just have pale, menacing faces. This makes some sense too because we only see them when they are about to engage in mortal combat with Geralt. Whoreson Junior looks like a rat, but he is definitely not the ugliest of the Big Four. That honour is claimed by Dijkstra. Dijkstra himself says many times he's ugly as shit, and I agree.
Like I have said, I have not played the previous games nor read the books so I shall not comment on character in depth. However, to me, it is "blindingly obvious" why Geralt does not kill Emhyr. Emhyr is the ruler of the most powerful empire in the Witcher world, and Geralt is not out to declare war on all of Nilfgaard.
Even throughout the quests to kill Radovid, he repeats that he does not want to be the hand that strikes the blow, and often tries to distance himself from the plot. Geralt does try to remain neutral, but there are big factors involving those he knows. Radovid has persecuted witches - one of the main quests is helping Triss escape Novigrad. Geralt is close friends with Roche, who is determined to kill Radovid for Temeria as it was. Not to mention Radovid's attack on non-humans, which affects people like Zoltan and Dudu. Honestly, from what I have seen in the Witcher 3, Geralt has far greater cause to despise Radovid than Emhyr. Emhyr is just a prick.
2. Not enough meaningful choices.
To be honest, I have to agree with this point. For an inexperienced gamer, it was refreshing to see any choices in the Witcher 3, and even better to see meaningful, difficult choices. I do wish there had been more choices like that which had a greater impact. I dislike the argument that side quests are meaningful too. They're not. You deal with a bunch of peasants and decide whether one lives or one doesn't. The werewolf quest you mentioned was interesting (I let him kill her) but typically they're just peasants. I don't really feel any guilt in accidentally making the wrong choice.
There are a few choices that allow you to make choices that are downright evil though. For example, you could have chosen to let the stableboy burn at Crow's Perch. That is perhaps unexpected of a game.
3. Politics is dumbed down
Again, I don't know enough about the Witcher world to comment in full. What I gleaned from playing is that Radovid is leading a Redanian uprising against the crushing might of Nilfgaard. Radovid promises to restore the sovereignities like Temeria but probably won't. Nilfgaard are favourites to win the war. The Blue Stripes are guerrilla fighters prepared to do anything for Temeria.
I have read replies about why the complexity of the politics was changed. Overall, I just think that politics is not necessary in the Witcher 3. The Witcher 2 was about political intrigue and movement. The Witcher 3 is not. It is understandable that you preferred the shadowy, intricate backgrounds in the Witcher 2. But that is not the type of story The Witcher 3 is trying to tell. The Witcher 3 is, as many have said, a personal story. It is not CDPR's fault that you prefer the former. They have crafted a Witcher game that is as authentic as the previous ones.
4. Sex is not sexy enough
The women expose breasts. A lot.
There aren't actually many films that actually show the actual genitals in action, despite carrying the 18 certificate. CDPR certainly didn't need to tone down the sex, but it's not meant to be pornographic either. The biggest sin here is the copypaste of sex scenes. It is a little bit disappointing that the actual sex was all one set. Even worse, the moan every female makes is the same voice clip. Ghastly. Couldn't the sex have been more romantic with Yennefer and Triss? They could perhaps have been a bit different for when Geralt is making love to his soulmate and when Geralt is having fun with a prostitute.
The Sabbath - I'm not really concerned. I didn't even read that text anywhere in the game. Human flesh. Yum, whatever. We went there to kill Imlerith and the Crones.
The most irritating flaw in this part of the argument is the complaint that CDPR did not do non-sexual nudity. Yes, they did. Whoreson Junior. That was very disturbing and they included nudity in that section to great effect. Although I do agree that the sauna scene was a disappointment. I find Ciri to be the most attractive female in the game. I'm 99% sure CDPR just added that as a cocktease. Pricks.