The reasonable set of ground rules seem to favor states over the will of the majority of the population. It is possible to change the constitution with states representing only 25% of the population. And remember you'd only need a majority in each of those states so could be way less of the population.

Overall the system seems flawed in that instead of having clearly delegated areas of responsibility to states and then doing the federal system as based on the population of the whole country it muddled areas and then made a federal system that couldn't respond to the population.