For everyone complaining that this wasn't "He-Man" and we didn't get much He-Man, you're right. It's Masters of the Universe and we got plenty of masters. So, you're complaining about the wrong thing.
That being said, the biggest problem with this show was the character lines. It started out really clumsy with all of the attempts to make puns on stuff related to Masters of the Universe.
For the good stuff, the artwork was beautiful. The story-line was acceptable if we consider it as it was intended, an extension of the original series. That is, had this series been released as a movie in the 1980's with the original animation, it would have easily fit into that story line, despite its darker tone (although, it seemed as if it drew more on the 2002 series than the 80's...). That darker tone is what's needed for a more modern story.
Over all, the series was better than it was worse. I'm rating 4/5 due to some of the questionable scripting choices with regards to the character lines.