Honestly, given some time to settle in as a norm and for the rest of the system to accommodate, “ideologically united parties plus medium-strong party discipline, with a 60-vote Senate requirement, though parties holding all 3 branches can pass one bill per year with only 50 but it decays after 10 years” might even be a workable system

Hell, if you “normalize impeachment” as a vote of no confidence, you’re halfway to jury-rigging a Westminster system