I am thinking that if there was no charge there would have been riots in the streets and it would have gotten really ugly. If she had charged him with something less then 2nd degree a jury might have found him guilty of that. But she knows he is not guilty so she charges him with something high enough that she is pretty sure a jury would never find him not guilty of.
I agree. I think you've covered it. It's actually a very smart plan, because it's a defense against the REAL attack, which is not against Zimmerman, but a political sabotage designed to incite race riots by the filthy Democrats as part of a political attack against all of America. They think they've got it nailed - damned if you do, damned if you don't. But nobody - absolutely nobody in the universe - can stretch things out into nowhereland like a prosecutor's office. And that's exactly what's going to happen here. And when the street racists are long bored out of their tired little vicious minds, and Obama's long lost the election, Zimmerman will finally be acquited - in peace.