Again, I concur with most of your arguments.
As to your 2nd point, if Bitcoin is made illegal somewhere then the value will soar.
However, I disagree with this.
Let's assume bitcoin is illegal in the US, but legal in other countries. Legal exchanges exist in these countries.
Could you explain why you think illegality in the US would increase the world price of bitcoin?
It could become more profitable to export/sell bitcoins to people in the US. This would be akin to the aggressive enforcement actions of the DEA raising the market price of drugs. Yes, the drugs in question are illegal just about anywhere, but not all countries enforce the drug laws as harshly as the US (and of course there are a few, e.g. Singapore, that are a lot more harsh than the US!).