Ranked Choice multiple member district mixed member proportional is the way to go.
This is what we need to get on ballots in states let me explain how this works.
Hypothetical state has 400 legislators (both houses) and say 10M people.
The state is split into 100 districts using the shortest line system (splitting the population equally down the shortest path until you get the number of districts you need.)
Each district elects 2 people. Each Candidate must reach 50% if a party gets MORE than 50 then the 2nd choice of the votes tallied after they reached 50% are given to other parties. Which means if a party gets 60% then 10% of those votes will be given to other parties based on ranking.
Voters will also vote for a party. The parties will get seats allotted by percentage of the vote. If a party gets 25% of the vote they get 50 out of 200 seats.
The result is a split legislature with roughly proportional representation while having representatives of districts as well.
Article from r/Libertarian: For a Free Society