i personally think the AI we are all afraid of is the mind itself.
we are not our mind, as is demonstrated by the ability to be mad at oneself.
the mind is doubt, the doubt is the veil that allows us free will.
ego is running things around the world right now, it is seeking to control everyone and everything. (it does this out of fear)
the mind itself is a shared mind, proven (i think) if you research calculus, you'd find it was developed by two people at the same time.
both accused each other of theft, but upon comparing notes they dropped all theft talk. both recognized the other as having found it on their own.
this is the foundation for these ideas i have, it seems more plausible, to me, than mechanical machines taking over.
the ideas you present would require us to forgot the risks and allow our decisions to be dominated by the AI (or implanted in us... no thanks! ) or perhaps given to military AI... ok that one is kinda scary.
ah well, nothing is really scary once you see we are all One.