As a long-time Nintendo and Mario fan, I can say with all honesty that this movie is a great story and love letter to Mario fans.
The characters are the classic characters we all know and love, albeit with some slight tweaks to improve the story a little. The character designs are also quite faithful to the games, however with a more cinematic flair added, and the animation is AMAZING and super high quality! There's also some genuinely emotional parts of the film, such as the scene where Mario protects Luigi when they were babies. While the humor wasn't as strong as I was expecting, I did get some good chuckles and laughs out during the movie.
The music is great and has lots of subtle references to the most well known games, and since I'm a long time fan, I recognized almost all of them. Melodies such as Bomb-Omb Battlefield, Gusty Garden, the classic Mario Bros theme, and more are present, and lots of Easter eggs as well for people to find. However, some of the references I'd like to be a little more deep, in terms of story or character building, but what we got is a nice middle ground, it's better than nothing.
All the voices are great, while I'm still a little upset about Chris Pratt as Mario, but his performance was pretty good. All the other voices are perfect in my opinion. I would like to see an edit of the movie with all the original voices included, as Charles Martinet as Mario would've been much more fitting to me, I mean, Charles is a voice actor by trade! However, I'm pretty sure both I and lots of others spotted his cameo in the film (which I won't spoil so you can find it).
The story I was expecting more of an origin, such as Mario's and Luigi's childhoods would be explored. But the story we got was good overall as it tells us how Mario and Luigi found their way to the Mushroom Kingdom. The story overall has a great premise, and I believe the message is about family and sticking together in a new place, as well as proving you can help when needed.
If I had some criticism, I'd say the scene where Bowser sings to Princess Peach is a little out of place, and goes on for a little too long, but it was funny regardless. I also of course have the gripe with the voices, such as Chris Pratt, but I can say they did a pretty solid job, for cinematic's sake. I'd also want more time spent with the different kingdoms besides the Mushroom and Jungle Kingdoms. I would've LOVED to see the Yoshi, Desert, and Ice Kingdoms, but I guess they didn't have any story beats.
Overall, I give this movie a 10/10, while it does have some room for improvement, what we got js pretty solid. And I can't wait to see if there's potential for a sequel or a different movie on another Nintendo franchise, I'm looking at you Legend of Zelda!
If you love Mario or Nintendo, go give this movie a watch, you won't be disappointed!