Frankly, the only reason BIG is not adopted by the power centers is that they do not (yet) understand how well it serves their purpose. So proponents should maybe change their strategy: In addition to explaining to the sheeple how they get goodies, they should explain to really powerful people like Cheney, Haass and Schäuble how BIG can be used to centralize power.
How would a well balanced BIG empower the government? It would simplify so much and make the government much leaner.
It requires much higher taxes and/or central planning, as this thread' poll suggests. It will result in even more involvement of govt in every day life. It will result in more tax evasion and thus a war against tax evasion. I'd expect the prison population of BIG countries to exceed that of the US today if BIG is financed through taxes. If, for example Switzerland were to introduce BIG and finance that partly through VAT, the current habit of Swiss people to shop and fill the tank in neighboring countries can no longer be tolerated. Bern will need more, much more law enforcement.