I’d also like to note that there should be a system put in place to ensure that justices can be nominated and approved in a timely manner.
For example (and only for example - I’m not presuming this to be a perfect or sole-existing solution):
General Statement: No person can be nominated twice.
Stage 1: Upon a justice’s seat becoming vacant, the President shall have no more than 1 month’s time to nominate any number of persons to fill the seat. On failure to submit at least one candidate, during this one month period, the duty to propose nominees shall fall to the Chief Justice of the Supreme Court.
Stage 2: After a nomination is sent to the Senate, they shall have no more than 1 month’s time to vote to accept or decline said nomination - with the assent of 60% of eligible Senators required for acceptance.
Stage 3: If, after 2 months, the seat is still vacant then each member of the Senate shall, secretly, write the name of a fellow Senator down, who they desire be excluded from the selection process. In descending order of the number of exclusion votes, Senators will be excluded from any further votes on any governmental appointments - in perpetuity - until 10% of eligible Senators have been selected for exclusion. When vote counts are equal among a group, they shall be removed by random process from within that group.
In addition to the previous, any previous person who has nominated or had the right to nominate justices shall be ineligible to nominate judges. Instead, this duty falls to all persons who have, to this point, been nominated and who have not been marked ineligible. Each such individual may now submit nominees of their own to the Senate.
This process shall repeat at Stage 2, with a fresh deadline of 2 months at which point stage 3 will be repeated.