Back track all you want, the only that fits the items 1-6 that you listed as applying to all electrical storage is batteries.
Apparently you believe the only "good" method is one where there is no cost and 100% recovery. You must also be under the assumption that power generation itself is 100% efficient and free of all negatives.
For storage to work it must only be able to displace power from base load pricing to peak pricing at a margin that exceeds costs. Regardless of how "poor" you think that method is the fact is there are hundreds of technologies that can not only do this profitably but with very little operating costs. The hydro pumping method has been in active use for over 50 years at a particular location in the US.
But go ahead and be a negative nancy for all I care, just don't deny your list and your assumption was batteries because no one looking at that list is going to believe otherwise. Don't you wish slashdot would allow you to go back and edit that list so you can put in all the things you learned about when you actually googled energy storage technology and learned about some of the proposed methods? That way you could cover up the fact that you ranted off about something you knew nothing about.