I agree with most of your points, except with volatility. If bitcoin becomes a global currency then it will have a much higher market cap than now and global support. This means it will have equivalent volatility to the dollar or euro. As adoption increases, volatility decreases.

"the lack of connection to something physical" - one can also argue about this. Money in your bank account is pretty much virtual too. If everybody right now wanted to withdraw their money from their bank account into physical money, we wouldn't be able to do that. There just aren't enough paper notes. Far from it in fact, it wouldn't even be remotely possible.

The biggest hinderance to bitcoin becoming a global currency in my opinion is the fact that governments are very scared of having a currency which they cannot control. Printing money is a wonderful thing to have for governments.