I finished with Death Note today. Very good overall.
The first 16 or so episodes were my favourite section. It lost a bit after that for me, because of the dynamic shift. Light got rid of the notebook and forgot for a while, so there wasn't that two way interplay between Light and L, and no Ryuk to lighten it up either. I felt the same section of the story was also a bit of a lull in the second Death Note movie, but it was much shorter in the movie, so I felt that worked better.
The movie omitted and changed most of the plot from Light getting out of isolation onwards, so that was all new to me. I don't know if it was for that reason I didn't enjoy a lot of what came after as much, or whether it just wasn't quite as strong. It got better once Light got the Death Note back, but the plot with the business men wasn't as interesting, and it got a bit unfocused imo once Kira became someone else. There was some great stuff once they went to trade the notebook in America, but the dynamic between Light and N felt like it was trying too hard to recapture the original Light/L dynamic, except without the factors it had with L being in the same location, and having the time to figure it all out, and knowing each other more personally. I liked N, but Mello was kind of worthless.
It also started to get confusing with all of the Death Notes with which one was where, and who could see which Shinigami etc. The last few episodes were great, and there was so much tension at the end of the second last episode, I almost couldn't watch, because I knew Light's plan wouldn't work. Light's downfall played out completely differently in the movies, which was better in some ways, and worse in others. I preferred that the movie ending included the original L instead, and without spoiling it, it felt much more fitting for his character. It also unfortunately introduced a couple of plotholes to the ending that the series didn't have (or maybe I just didn't notice them in all of my confusion about the Death Notes). I'm admittedly probably a bit biased by having seen the movies first, but both were an easy watch for me.
So I guess next up is Parasyte.