"Rule of the urban majority mob would be a lot worse than the current structure."
That's pretty clearly only your opinion and not an obvious fact. Urban centres tend to vote for more progressive policies in the US, so all you're saying is that would be too progressive for your liking.
But who says one region matters proportionally more just because it's bigger? Isn't society all about the people, so isn't it the people that matter? Are you really saying that it's not about being a person, it's about how much land you have?
Besides, what this imbalance really does is allow national groups to game the system. By focusing lobbying/campaigning efforts in smaller states, you can gain influence in government more efficiently than by trying to influence the high population regions. Which distorts the importance of those small states even more...
That's pretty clearly only your opinion and not an obvious fact. Urban centres tend to vote for more progressive policies in the US, so all you're saying is that would be too progressive for your liking.