The only change we need to the Constitution is an amendment to limit the 44th president’s term to 12 months.
I’d make a change to have the Supreme Court Justices serve 18 year terms, not life. Every two years, the President picks one. If one dies or leaves office, the sitting President picks a replacement to complete the term. Justices may serve for more then one term is reappointed.
It would really make the Presidency far less important, and voters would know exactly which Justices were going to be replaced by the next President.
It would also avoid the inventive to pick young unproven justices. Pick a 60-year old to serve until 78. It would end the geriatric issues, too.