I watched it, now, first of all, I acknowledge that it is NOT AN ADAPTATION and therefore will be different, but it still has issues and the fact that it might get a sequel is a kind of insulting to the source material.
The first issue, Light Turner, reputed as a genius yet acts like a common punk. The only time any genius is displayed is during the ending (this is how they bait a sequel) so it's really cool so sequel maybe? No. Honestly, he was stupid for bringing the girl in on his secret, and how is he so easily charmed? If he's really as smart as they make him out to be, his character lacks the healthy skepticism and also a touch of common sense. Common sense would tell Light "the law isn't absolute and you know it's broken or weak so best not to threaten bullies with legal action" and he then proceeds to do so and is knocked to the floor as he should be.
Second, the character of "L" and also Watari: Again I know it is original but hear me out, Watari was killed with his codename! They broke the rule of the death note in their own movie, why would the greatest detective in the world have his handler use his real name if he had deduced how Kira kills, and speaking on that, "L". I have to ask, why does "L" seem to have a hyperactive sweet tooth that borders on extreme OCD? Why and how is the greatest detective shaking all the time? Why is he so reckless?
Film makers are apparently out to take great ideas and then repitch them with awful edits to people who don't understand why the source is great, to begin with.