Sonic movie was actually nice. I don't watch many movies so I'm not sure how "good" of a movie it is, but I liked it a lot. I feel like the main characters had depth to them, the jokes were funny, and the plot wasn't completely predictable.
The movie was corny in some spots, but it wasn't too bad. Sonic's super speed was shown off in a lot of really cool action scenes. At no point did I cringe while watching the movie. The movie's music, when referencing Sonic, always went back to Green Hill Zone, disappointingly.
I feel like Sonic's voice acting fit his personality and his OG character well (what I mean by that is that Sonic in the movie is consistent with Sonic in the games). The CG in the movie was super colorful and nice to watch.
Tom (human sidekick) played his role very well--he didn't completely overshadow Sonic and make the entire movie about stupid humans nobody cares about (they did a good job of focusing on both Sonic and Tom, as well as making you care about both characters).
I really like the overall plot, the portrayal of Sonic; even though this version of Sonic isn't canon (what even is Sonic's canon?), it's a very solid story that can stand on its own merits. I'm excited to see a sequel featuring more Sonic characters, maybe the Chaos Emeralds, Eggman in his even more crazy game-like form, etc.