These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Warrior Cats: Dawn of the Clans
Alas, Poor Scrappy: Before the release of Thunder Rising, Moon Shadow wasn't that well liked a character. Now, his former haters are mourning his death.
Awesome Art: The cover art of The First Battle is just amazing.
The time period of the series. Some fans like the idea of a prequel and think The Last Hope wrapped things up well, while other fans want to know what happens after the battle. However, it appears to be dying down with the positive reception of The Sun Trail.
The treatment of she-cats in The Sun Trail. Some fans think that the she-cats got shafted in terms of character development and the book is full of misogyny. Other fans don't agree and think the complainers are just being obsessive.
Come for the deaths, stay for the character development.
Come for Gray Wing, stay for Tall Shadow (or Jagged Peak).
Continuity Lockout: After the amount generated by Power of Three and Omen of the Stars, this arc for the most part avoids it. Someone with no knowledge of the rest of the Warrior Cats series could pick up a copy of The Sun Trail and completely understand it. However, it still exists in small qualities. If this is a reader's first Warriors book, the beginning scenes featuring the Tribe will lose some of their impact, and the last chapter's rather awe-inspiring reveal about Thunder will fall so flat that new readers won't even realize that it's a twist.
Some fans admitted to reading The Sun Trail solely because they wanted to see River. Subverted in that he's the only Clan founder that didn't show up until the second book, Thunder Rising. Then fans could enjoy his presence.
Quite a few fans only read the book because of the beginning scenes with the Tribe.
One-Scene Wonder: Nightheart showed up, spoke two lines to Gray Wing and Clear Sky, then swam off. A fanbase was born.
Sacred Cow: The Sun Trail has become one for fans. Bash it at your own risk.
Win Back the Crowd: After the lukewarm reception of The Last Hope and Yellowfang's Secret, The Sun Trail's return to a plot driven story and fresh ideas made a lot of fans declare it one of the greatest books in the series.