Why should a centralized government be smaller? It probably mostly depends on the services a state provides. When the state provides services as public transport for all villages, there needs to be a fund for this, when the national streets are maintained in contracted from the government, there needs to be a fund for it. For Schools, for Military, for Police, for universities and science, for independent press support, for local farming, open provided statistics for all within and out of government.

These are all Services we invest in our society in Switzerland. And it is payed by taxes. Which does not mean it is all government. It is a system to pay services collateral. It is a social investment, I pay happily. Since all profit from its fruits.

And when the government wants to expand the budget in some direction everyone gets to vote about it. Like this we have a very close connection from voters to politicians. Every year we vote for about 12 legislative changes, where every swiss citicen can participate. Plus the local votings. 

 I hear very good things about the swiss democratic system, though I also hear that lately the central banks have been able to corrupt even that to some extent?  

 I mean also in switzerland there is corruption. But I think corruption is something a society has to minimize with good rules. So that the corruptable regret it sooner or later. When most corruptables regret it hardly I think the rules are quiet well. 

I do not beleave, that there is a way to prevent corruption.