Top-two primary and/or ranked choice voting to start. I’d also like to see the popular vote compact come into play for the presidential election. Eventually, for Congress I’d like a hybrid system that accepts the existence of parties so it can manage their worst impulses and give representation to smaller constituencies.

For the remaining geographic regions, set a certain standard for mathematical compactness; this doesn’t have to be too aggressive, as a long thin district can be completely sensible, but we don’t need the devil’s fractals many places have now. Also/or require districting committees to try to draw districts that would roughly approximate the state’s popular vote percentages. We know they’re excellent at isolating voters by party, so let them, but force them to play around on the edges to get one seat here, or get out front of some changing demographics here, not the wholesale cracking and packing we see from both parties now.

It also all needs to be legislated at the federal level or even by constitutional amendment, but honestly we’re kind of fucked. The people who need to be reined in the most very much live in states where they are overrepresented in voting power, and I don’t see them giving it up.