I’m strongly in favor of abandoning FPTP everywhere, etc., but I’d caution against tying hopes to a single cause. IRV/STV/RCV/PV are used around the world, and their effects are not that revolutionary. (My softly preferred approval voting sees least real world use, either way I’m not letting my fantasy run wild.) Politicians, parties and voters adapt to the new ruleset, and in the end some form of median voter theorem still rules (Two coalitions dominate, fighting around the center.) The US system legal and geographical pecularities mean, in broad strokes, that it’s a median voter in a median district in a median state. On the party side, the system shifts much of the coalition-building to significantly before the elections, in comparison to other countries, where it’s done close to or after votes are cast. But then, I too believe we can and should do better.