Then she should get an agent if she's that into acting. After all, I think it is common sense that they'd go through agents first before inviting the public to audition. They also wanna make sure they get people who actually want to be actors and who want to act rather than just people who want to be in HP and who constantly stare at the camera.

Personally, I don't see how or why they'd cut Luna. Her role is just as important/unimportant (whichever way you view it) as Neville and Ginny's. I don't think they would cut her. If they did, then surely that'd call for the cutting of Tonks' character, seeing as she's even less important than Luna?

I can see why Michael might be cut. He can simply be referred to without us ever having to actually see him but Luna has quite a hefty part. I don't see how they can cut the supporting child cast.