Focusing on democratic nations specifically for a moment - I don't see how it could be a balancing weight. Presumably all issues with a country and its handling of their own currency could be resolved solely through democratic political means.
No technical solution - cryptocurrency or otherwise - necessary.
I don't really understand your second point. Taxation by definition is involuntary. I won't discuss the merits of taxation (vs. detriments) but a "voluntary taxation" system would result in a prisoners dilemma where no one would pay taxes. Eventually the government that implements such a thing would be no longer able to fund itself and in quick succession find itself literally bankrupt.
No technical solution - cryptocurrency or otherwise - necessary.
I don't really understand your second point. Taxation by definition is involuntary. I won't discuss the merits of taxation (vs. detriments) but a "voluntary taxation" system would result in a prisoners dilemma where no one would pay taxes. Eventually the government that implements such a thing would be no longer able to fund itself and in quick succession find itself literally bankrupt.