I also want them to succeed, but I don't think it's a bad thing to question/criticize choices they make --- it's one of the fun parts about being a fan of a thing. Most of my criticism comes from a place where I've read way more of the lore than most people, even casual fans.... so I recognize that. I think the show will succeed or fail based on the quality of the writing and story telling. People like me who love the lore and story, will be able to accept changes as long as it's well done... doesn't mean I'd rather see it a bit more consistent with the story I grew up with.
I also feel like they could be writing themselves into a box unnecessarily. For example, they only have the rights to the LotR and the appendices right now. They are allowed to request more IP in the future, and if the series is successful, which I hope it is, they can probably get those rights... so Galadriel's rise to power is really a First Age story -- she also wished to rule a kingdom and though she did not swear Feanor's oath, and opposed the Kinslaying, her heart was stirred by the desire of adventure. She is a great counterweight to Faenor. While not as powerful she is wiser, but she also is proud and has her flaws -- she's a great character. So, if Amazon gets the rights to the First Age, she would make a really really good character to follow -- but if it's in this continuity with Amazon, you have to have her end up as merely a leader of the nothern Armies of the High King (and apparently only recently promoted based on her conversation with Elrond in the first episode). That would be a huge step backward from where she ended up in the First Age if we ever get to tell that story.
Meanwhile, in the LotR and appendices, we have the character of Celebrian. Galadriel's daughter. Not a lot is written about her -- so you can do a lot with the character. All we know about her is that she marries Elrond, at some point she is captured by "the Enemy" and tortured, and is rescued by her son, but the damage to her soul is too great and she has to go West leaving Elrond and her children behind -- very tragic story... but that doesn't happen until the 3rd age. You could do all sorts of things with her in the second age....
This is obviously super dorky, and there's a good chance we'll never get to First Age story telling, so my concern with writing Galadriel into a box might be overthinking it... but I would be curious to hear why they made certain changes, because they did employ Tolkien scholars to work on the story, and they obviously know everything I talked about. My concern is they used Galadriel because she's more well known and more marketable -- and I don't think that's terrible, they still have to sell the story to casual fans and not just to super nerds like me... but I hope there are other story telling reasons for doing what they're doing.
But as I said, as long as the story is good, the script is good and the acting is good, it'll be a successful show.