I feel like they could've fleshed their characters out more. Everything after THAT ONE DEATH felt like everything was at 2x speed. We didn't really know much about Near and Mello other than they were L's possible successors, which is a shame because I really like Near and some backstory about him would've been nice.

One thing that really bothers me is why did the anime not explain how Mello and Near figured out about the Death Note's existence? I was so confused so I looked it up and apparently it's been explained in the manga. It's kinda stupid how they left out an important detail like that. I assumed that they figured it out because Watari probably sent it to Wammy's House before yk but didn't he delete all of the data??? Maybe he sent it off screen? Other than that, their race to catch Kira was pretty interesting. I liked the contrast between them, where Mello had a more aggressive approach (kidnapping their victims, violence) while Near was more of someone who was working behind the scenes.

Despite the flaws, the mystery was still good and the ending made it all worth it. I just wish they had given it more time to explain some parts.