Okay, um, where to start with this...

I'm sorry, but the Alter Ego really does not fit. While I did say I don't mind villainous ones, because some personalities can be expressed in a negative way from exaggeration, this seems... not quite what I was really expecting for those.

For one thing, the whole clown motif is a little baffling for me. Even though I did say things can be expressed through an Alter Ego, well... for example, Mio and Black Storm Barrage. Mio likes an idol. Black Storm Barrage has no reflection on this trait and is instead based around personality traits rather then things Mio likes. And the one case where Black Storm Barrage is based around one of Mio's preferences, it's that she likes ice cream. Liking clowns wouldn't make your Alter Ego look like a clown, no more then Black Storm Barrage looks like an idol or ice cream.

Also, Alter Egos... aren't animalistic, that's really the best way I can put this. They look and act human. Even unstable, an Alter Ego still uses their weapon. Though their weapon might change form or something. The biggest potential differences an Alter Ego can have is an exaggerated appearance in some way, or maybe, like, um... I could see one having claws or horns or something but they still act like a person. They wouldn't act like some kind of monster. And the vast majority do have some kind of weaponry. Also the naming scheme is off. Alter Ego names are more like... the closest that could even get to what you had would be something like "Saw Bone Blade" or something. Their names are nothing like what you would call a person.

Also, you don't give any idea of limitations for her abilities at all.