And why is it a plot whole that Astarion is a living vampire when some crazy, twisted shadow magic is changing all the rules? He is now quasi alive and quasi-dead. I think it makes his story interesting and unique. I want to know how and why and so forth.
I never meant for Astarion walking around in the sun to be a plot hole. I said it made no sense for him to not realise that the triangle/skull motif is Myrkul's symbol. He must have been in a crypt half the time he's been around Cazador, and I bet there were some leftover symbols etched into the crypts. Besides, Myrkul was the god of the dead for a good 100 years or so after Astarion was turned, so even if Cyric and Kelemvor decided to erase all Myrkul's symbols off the face of the Prime, he'd still have seen it. Instead, he just says "meh, I wonder what it is". The party knows about Bhaal and even Jergal, but not Myrkul?
Now, again, if I get to the end of the game and they never explain it, then YES. I'm going to say this game went from my all time favorite to a piece of trash real fast. If by the end they don't solidly explain things, that's bad, and THEN I will never play another Larian game again. But right now? It's way to soon to judge.
If they explained WHY we can't do the headbash method, then it would make sense. As of now the game universe is acting as if there's no such method, with Omeleum, Lae'zel, AND Gale about. Three people who know way more about ceremorphosis than an average mage in Waterdeep, one's an illithid himself, and no one says "hey what about this method?". The party's willing to talk to and drink weird concoctions from a goblin priestess so they're pretty desperate, but no one bothers to even ask about the method that seems pretty straightforward.
