I actually feel this was well adapted from the stage show by tieing it all together through the experience of an abandoned cat (Victoria) meeting the jellicles for the first time. This is the glue a film version needed to stick all the pieces together.
I admit that many won't be able to feel comfortable with the design and CGI of the cats, but I could tell what they were trying to achieve. If you can accept the design, it's a pretty spectacular world and a unique experience.