I'm pretty sure I'm one of the only few, but Echo definitely seemed to suffer Second Book Syndrome. Not in action or world-building, but in the characters and romance. And while everything besides those were wonderful, characters and the romance are big things for me, so it affected my opinion greatly.
The characters...they were so much more self-centered than in Fated. Dace was more egoistical, Daire decided she was Miss-Know-it-All (at least in the beginning) and we got introduced to new characters. At least two more! And while I love meeting new characters...one (Axel) was mainly introduced near the end so I was confused, one (Phyre) was apparently very important, but we literally find out near the end of the book how important. Or, rather, the book tells us. We already know how important when she was first introduced. And then some minor characters who you'll have to read to find out about!
Dace...wasn't as...sweet, per say. Sure he was adorable in some moments, but it's like he didn't really care as much about defeating the antagonist as he was about their romance and how he looked in Daire's eyes. When he (slight spoiler) failed to kill Cade, he was so ashamed because Daire was there so he went back AGAIN after being almost killed. Ugh. And Daire just annoyed me in this book, but it was how she acted overall, so I can't quite put my finger on what annoyed me.
The romance was so completely, utterly sappy. And I'm not a fan of those at all. I like my romance dark, forbidden, etc. But definitely not sappy. And while the romance had forbidden down, it was just so...like I said in my review of Fated, it was a bit too innocent for my tastes. And Dace and Daire...
Ex: "Content to just stand there and fill my eyes with the glorious sight of her."
Not my type of romance, I'm sad to say.
Now, the plot was just stunning! There were definitely twists I didn't expect, some completely out of the blue, but others just purely shocked me. Seriously. Alyson Noel may not have the best characters, but she knows how to spin a story! The pacing wasn't slow and I found myself flipping through it, despite character and romance issues! It continues Daire's story beautifully, alternating between Daire's and Dace's POV.
Short paragraph part: Love the world-building and descriptions! Seriously I wish I could live in the Enchanted Spring...when it's actually Enchanted and not tainted by the Richters.
Overall, I'd recommend reading a few chapters of Fated before you buy and if you liked that, buy Fated! and if you like Fated, buy Echo (obviously). It was a fun read that, while I didn't absolutely love, I did enjoy while reading. It's one of those in-the-moment books where it's good when you read it, but not as good when you analyze it or overthink it!