"Government doesn't work." -- Harry Browne

I'm no big Harry Browne fan, but he got that one right. A one-world government would be every bit as bad as what we have now, and probably worse, for precisely your first CONS reason. A one world non-government, the end of the concept of imposed authority, on the other hand...

Unfortunately, the current elite has a nearly perfect system for brain-washing the masses into begging to be ruled: public schools. The only peaceful option I know of is creating a parallel non-system, a plethora of agoras, that we hope will eventually supplant the authoritarian systems. Block-chain based currencies, like Steem, are a piece of that equation.