Honestly? It was an enjoyable movie for me. It's definitely an added bonus that Pikachu was such a cutie in that movie. The visuals of the movie were also great, which isn't surprising because of the technology today. Those scenes with Mew were cool to watch, too.
My only gripe was with the writing and acting. I don't think those two held up to the same standard that the movie's visuals brought to the table.
