The main criticism is the destruction of KNOWN characters and their personalities.......Galadriel is chief among them
You see this is what I find so interesting about your criticism. You base it on your view of the Lore, which is incomplete.
1) The only definitive Galadriel we meet of the professors is in the LOTR, which includes the appendices written statements of her rejecting/being suspicious of Annatar.
2) Every other element of Galadriel is speculation from the vast Silmarillion materials. Those materials, which cover her earlier life, posit her as a warrior fighting at the Kinslaying and rejecting Feanor and leaving for middle earth on her terms. It is entirely clear to me that the show runners, as well as basing her story on her words of rejection about Sauron, were inspired by these speculations of Tolkien.
What is ironic about all this hand ringing is when the professor wrote the Silmarillion and Akallabeth Galadriel did not exist he had to 'wait for it' write her back in afterwards.
The early warrior Galadriel also coincides with his knowledge of Haggard's Ayesha. In her early life she rode with her father's warriors and fought in her back story, much as Galadriel at the Kinslaying.
I am afraid I will not be able to join you in your play room today, I am out hiking and scuba diving. (Humour).
