As someone who really loves Kill La Kill and Gurren Lagann, I have to say that while this was a fun movie, I had a really hard time connecting with the characters. It felt like Trigger was trying to drop us in the middle of character development. Galo could never develop Kamina's charm in only a feature-length film. The visual action and directing were as great as you'd expect from Trigger, but even though the music was GORGEOUS, I felt it hard a hard time really captivating the moment (with the exception of beautiful piano song played behind Lio in a couple scenes). I did ultimately like the theme of the movie a lot but I felt the ending could have been a little better.
This is a good movie and it's absolutely worth seeing, but I don't believe it is the masterpiece that other reviewers seem to imply it is. I really think this story would have benefited the most from a full (single-cour) anime series with the movie's contents compiling roughly the second half.