We should amend our Constitution to establish nine Supreme Court Justice seats, each having an eighteen-year term, staggered to begin one of the nine seats every two years on the first day of October of odd-numbered years.
This regimen would ensure that Supreme Court appointments may be thoughtfully considered by the electorate during each regularly-scheduled election in November of even-numbered years, and it would guarantee to each new four-year presidency two regular Supreme Court nominations, and to each new six-year Senate class three regular Supreme Court confirmations.
The President should be required to send three nominees to the Senate for their consideration by the first day of April, and the Senate should be required to confirm one of these three by the first day of June. Failure by either the President or the Senate to meet these deadlines should result in the offended entity being granted the right to appoint immediately the new Justice without input from the offending entity.
In no case should any regularly-appointed Justice be eligible for re-appointment to the Supreme Court. If the number of active Justices should ever fall below nine, then a special appointment process should begin that day with the President having until the sixtieth day after the vacancy begins to send three nominees to the Senate, and with the Senate having until the nintieth day after the vacancy begins to confirm one of these three, with similar penalties for failure to meet these deadlines. Specially-appointed Justices should begin their service immediately after their appointment. No specially-appointed Justice who has served more than nine years should be eligible for nomination to the Court. Thus, the longest any person could conceivably serve on the Supreme Court would be twenty-seven years.
In practice, the office of Chief Justice of the United States has proven to be minimally administrative and largely symbolic. If the office of Chief Justice should be vacated, then an offer to fill the office should pass immediately to the most senior of the sitting Associate Justices who, within ten days, may elect to decline the offer, in which case the offer should then pass immediately to the next most senior Associate Justice, and so on. The Chief Justice may, at any time, elect to vacate the office of Chief Justice without abandoning their seat as an Associate Justice.
This new regimen should begin immediately. Until the nine current Justices vacate their seats, their lifetime appointments should be honored, which implies that the Supreme Court may transitionally have more than nine Justices, with conceivably, but unlikely, up to a transitional maximum of eighteen Justices. No doubt the Supreme Court will endure its Justices sharing such a temporarily crowded bench.