I won't speak for the world as a whole, because I doubt anyone here knows much about it that way, but as far as the US is concerned, I would create a new voting system that would do away with the stupid electoral college, and create a system where people can vote for anything new that arrises, whether it be a new president, or a new law, citizens have the majority say in the vote of how things are run. This is mainly due to the fact that I am getting completely sick of watching this crap back-and-forth nonsense between both political parties. Sadly, this won't happen anytime soon.
I guess that kind of voting system would work well in any area of the world, though.