The options I listed in my first post are still the only options. If you don't want to filter out SD transactions then the default "do nothing" option means that transactions will become very expensive, and small quantities of Bitcoin won't be spendable at all.
Not really.
Just expensive enough so SD is not viable. Say, 0.03 or so. For a moderate quantity it's not expensive. For micropayments, BTC is never going to scale to global scale as to accommodate micropayments. It's simple math really...
I don't think BTC is ready for fees so high. That's going to shut out a lot of commerce, not just SD.