I think it would become more proportional, but there would be proportionally less competitive districts. It's harder to draw competitive districts when they're confined to a small geographic area.
This. It's what occurred whenever I did various hypotheticals with the DRA data between 2016 and 2018. The other thing is that increasing the House's size is a comparatively easy way to lower the Electoral College vote strength discrepancy between the large and tiny states.
That isn't the main problem with the electoral college, though.
