"Vote for 1, Top 2 Win"

In the short term (0-1 years), we'd see districts elect either two standard Republicans, two standard Democrats, or one of each.

In the medium term (2-7 years), I think we'd see districts get a choice between a conservative, a moderate, & a progressive, and elect 2 of the three.

In a longer term (8+ years), I think we'd get a real third party that stands for different things than either of the Republicans or Democrats. The political spectrum would change into a political triangle, each party having a base in one corner & competing to win over the voters in the center and on the sides between each other.