4. Better competitor crypto currency with some technical advantage, like speed - Could ethereum replace bitcoin?

This. With a slight twist. Inefficient forward-progress of Bitcoin development, innovation, and protocol enhancements. This is my concern.

-B-

Valid concern. So much money flowing into bitcoin ventures, but so little into protocol development. Angry

It is kind of amazing that this 6 billion dollar mammoth is head together by a few overworked and underpaid people, isn't it? Tongue