I understand that some people may not get a grip on the story and may have issues with the pacing with the movie itself. That being said, even the few cliches that the movie serves us are being treated elegantly. We have ballet dancers - and as we know already, ballet is nothing to be messed with. If you want to succeed, it seems you have to endure a lot. Physically and psychologically.
There are quite a few things that Black Swan might have done a bit better (to say the least, soundtrack definitely being one of them), but comparing those two movies would be a disservice to what this is trying to do. This is trying to shine a light on many different aspects and on many different people. While we never entirely lose the focus on the main characters, we also get motivations from one family involved (with our main character), the dance instructor, best friend, rival dancer and so forth.
Again that may feel like the movie took on more that it can chew. But it handles it quite good most of the time. And that ending - you could not have found a better moment. It is not just dreams that are able to fly ...