Politicians are there to manage things, so what is needed are good managers, the object is to vote in those who can manage the country best. Vote them out when they have screwed up too much.
Politicians are there to represent the public's wishes, and the ones that are the best caretakers of that should be voted in to make the system as democratic as possible.
Problem with the two party system is that two evenly matched parties are encouraged to compete for votes by outdoing each others electoral promises. This amounts to irresponsible party government, in that parties come to power on the basis of election manifestos that they have no capacity to fulfil.
Disillusionment and cynicism grow as parties seek power by proclaiming their capacity to solve problems and improve conditions.
http://www.cityam.com/article/cartels-politicians-do-not-serve-public-interest parties acting as a cartel.