What really matters in the goverment is the senate. Sure i suppose the house, the president and the supreme court is important, but the most important is the senate. The president is less important in that the senate+house can overrule them, and while the supreme court can declare a law unconstitutional, the senate+house can change the constitution. The deciding factor in weather a law will pass is usually the senate.
As it stands now, a vote from a person in wyoming (650 thousand people) is 70 times as strong in determining a senator then a person from california (37 million), since they both got two senators each.
If we changed it to percentage vote determines composition, and we kept it as every state got two senators (and did composition within each state), then we would end up with a 50-50 democrat/republican split senate, in which nothing would EVER get passed.
If we changed it to the whole country gets 100 senators, and percent composition was from the entire country, then each wyoming voter would get the same amount of voting power as a californian. Something that aren't in their best interests. In fact, the top ten states (20% voting power right now) have well over 50% of the population, so they would have by far the largest impact on the new senate, while the bottom 40 states (80% voting power right now), would have less then 50%.
So for any of the smaller states, it wouldn't be in their best interests, while it would be in the best interests of any of the 10 largest states.
But, the smaller states have 80% of the vote, and they are smart enough not to do anything that results in them having a smaller percentage of the vote.
Is that clearer (it might not be, and ill try to explain it again in that case)?