I've lived in both the most rural and urban parts of the US, and it's clear that the current system massively discounts the will of people in urban areas in this stated endeavor of providing some kind of rural / urban "balance".

Depending on what you consider urban, the US is roughly split 80% urban, 20% rural.

To me, it seems unlikely that a ground effort in rural America would be completely neglected in a proportional system. If a party did neglect the ~20% of rural voters, it would seem to put itself at a disadvantage to other parties, especially given the lower relative cost of rural media markets.

We see the same problem with the Senate, where populous states such as Texas and California stand at a remarkable disadvantage to Montana and Wyoming in terms of representation. The voice of a constituent in Wyoming is 66 times that of one in California.

How can we call this system representative?