The post Kaer Morhen stuff also didn't interest me as much. I think if they'd ended at Kaer Morhen the ending would've been abrupt. They should've finished the stuff with mad rad, allowed you to get some army troops from Nilfgaard, (as it stands Geralt refusing them is incredibly stupid) had some down time with Ciri, and all your old friends who come to help at Kaer Morhen, then ended on the battle with a victory at Kaer Morhen. Maybe have an RDR style post victory thing, where you get to see Geralt in his new day to day life. Be it with Yennifer, Triss, or just him on his own again as a
Witcher. As it stands the game continues on past this point for an additional 20 hours or so, which is somewhat unnecessary and only serves to belittle the story. In my opinion.
I was always nervous about how CDPR would handle interdimensional elves, to their credit I honestly think they did the best they could with it. But I think shifting the story focus from Ciri and the war was a mistake. I think there should've been more political stuff, and less space elves fighting unicorns. Honestly that part of the lore of the witcher is pants on head retarded, it should always remain an untouched thing. It's interesting when you don't delve into it, once you do the potential for stupidity is just too high.
The wild hunt should've remained somewhat enigmatic, and the only info you should've really gotten on them should've been what Av'alach told you. Keeping them as an unknown that you manage to defeat would've been a better choice in my opinion. As it stands Geralt is just world hopping like crazy at one point and you're waiting on him to show up at a Maccas or stumble into the Normandy.