... if one party gets 40% statewide, 40% of reps are assigned to that party, if the other gets 50%, they get half, the rest go to the third party or even to a third and fourth party ... or to a runoff if no other party gets close to a 'full rep' percentage of the vote! Make the house 449 or 499!
As an alternative, have a rep for each 600,000 voters, or within 5% of that number! It might lose a small amount of personal contact, but it may encourage more state loyalty rather than only district loyalty among the reps as they would be statewide candidates, answerable to all of the state's vote!