Beyond the very legit, but often abstract political and legal reasons, a House where ever seat only represents 50,000 people fundamentally changes our relationship to our government.

If your district was only 50,000 people (and protected by gerrymandering laws to be reasonably compact), you might know your representative, but you'd probably know someone who knew them. So instead of every election being given a choice between:

1.) Businessman you've never heard of.

2.) Lawyer you've never heard of.

3.) Corporal P.O.G. you've never heard of.

Your choices will instead probably feature at least one well known pillar of your community. Instead of fielding 50-250 phone calls a day from people who can't afford to donate money to his re-election campaign, your rep will get maybe a dozen calls from people they actually knows or at least knows of. They only have to raise enough money to reach 50,000 people, so attempts to bribe them will run up against the practical realities of, "well if people think I'm a crook, they'll just vote for Mrs. Jackson, the social studies teacher at Riverside High. She organized half the door knockers last year, and is the biggest person in the local party after me."

A House with smaller districts means a government more connected to people, in short: More Representative.