This whole obsession with altering the rules to make the system fairer is a distraction.
Look at every single country in the world that's not an utter tyrannical pile of waste, and you will discover a welfare state of some manner of description, with high taxes, regulation of every form of human activity, and so on, and so forth – no matter what shape their constitution takes and for how long their legislators are elected.
This suggests that the issue is not with the manner in which your legislators are elected. In truth, the issue is that in the first half of the 20th century, Progressives took over Western civilization. Some of them are right-wing progressives, from Frum and Kristol to Medved and Levin. Others are left-wing progressives, from Reinhold Niebuhr to Michael Moore. They are all the enemy. The radical left are probably less hostile to you than smooth-talking evildoers like Frum.
Over the years, progressive intellectuals, corporate big-shots (anybody who says 'he is rich, he must be for capitalism' is either an enemy or a fool), and politicians have created a semi-formal system, ranging through our universities, to our newspapers, schools, major banks, corporations, government offices, that is self-sustaining. This is not to say they 'cheated' – every society, including the one we want, will have informal self-sustaining mechanisms. But this is to say destroying progressivism is a hard work which will require risks, and effort.
The democratic system of rule is, informally, more conservative in the dictionary sense – more averse to change in the long term than a totalitarian system. A totalitarian system can be revolutionized when the dictator dies and is replaced by another dictator. Revolution in a democracy or a Republic takes decades and generations, placating numerous interests.... sound familiar?
If we altered the constitution in any way you like, and fired all members of both houses, and held an election tomorrow, progressives would still win. The majority of people elected would be in favor of a graduated income tax, a welfare state, and so on, and so forth. Hard work would be required to alter that, and applying that hard work to alter the election system will be simply a waste of resources.
It is not enough to merely vote. It is not enough to merely vote in the primaries.
How many people attend local meetings for their political party? How many volunteer for their favorite candidate before the elections? Answer this, and you will know precisely why the status-quo remains.