I will give the show a 2 star rating. That casting and writing weren't done very well, in my opinion.
Gabe was terrible. Sally and Gabe had a relationship that seemed like a normal couple, not a relationship just to keep her son hidden and alive. Gabe was a dirtbag and has his ending coming to him in the book, not so much the tv show. As much as I disliked the movie, Gabe was better casted in that.
Annabeth was ok, but she didn't give a vibe of Athena's daughter. She gave off more of a vibe like Clarisse from the book. I didn't like that. I have seen some reviews that admire her fire, but what I feel like everyone is forgetting, she is still a pre-teen. There was absolutely no admiration for Luke. No chemistry between her and Luke. The only time Luke really talked about Annabeth, was to bring up how she was like his sister. Which was accurate on his part. But the problem was, it was said and then Percy feels bad for Annabeth. Annabeth's crush made the betrayal that much harder. Which was needed and clearly we are not getting.
Grover was ok, but he acted to much like a child. He has already admitted that he is 24. He hasn't been acting like a child for that long, I don't think it would be hard for him to start acting like an adult.
Chiron could have been done better. Honestly, I felt his acting was forced and he wasn't really into it. Almost like he thought he was just going in to read some lines to audition and it ended up making the cut.
Dyonysus was too goofy. He wasn't goofy at all in the books. He was a grumpy old drunk that hated Percy's guts. Hell, he wanted to kill Percy or turn him into a dolphin for crying out loud.
The story is jumping around all over the place. They are throwing in stuff that could have been left out or that was never in the book, and then pulling stuff from the middle/end of the book and putting it into the beginning. It has people telling parts of the story that weren't the ones to tell it. And don't even get me started on the episode with Medusa. What even was that? They weren't supposed to know that Medusa was the lady. They were supposed to be tricked. And the Fury being there? Just no. She is supposed to be in the end to give Hades his Helm back. It was just all wrong.
I give this a 2 star rating so far, because some of it has been true to the book, more than the movie. But there is still so much wrong with this one. I feel like Disney had a real chance at making this better than the movie and I feel they are skating downhill. They have an opportunity to really give readers what they have always wanted. Use the books right. Use the chapters for episodes. Get the information in there. Stop putting random stuff in it that isn't needed.