I love how everyone is ignoring California's 50 Congressmen, compared to Vermonts one Congressman. The Senate and House counterbalance one another. The real reform needed is getting rid of the House's gerrymandering.
They were designed to balance each other, yes, but that was long ago when the differences in population were not this dramatic, and when the size of the House would grow increasingly with time. Since we've capped House size (which is, by the way, the Republican Party's doing), and gerrymandered districts more viciously than ever (from a system, again, passed by the Republicans in 1929), the balance is no longer effective.
To continue off of this: back when the system was created the size difference between the largest and smallest states was 11:1. Now it's 66:1, and the disparity will only continue to grow.