Hopefully they would be more insulated from the corruption and influence of special interest groups and political aspirations.
The USSC got it's first lessons in living document revisionism rammed down their collective throats by FDR and the New Deal Congress.
Much to the contrary they are their own special interest group and are wholly insulated from having to answer for their actions.
Why is a 5-4 ruling (which we see all the time) more comforting to you than a flip of the coin? Shouldn't constitutional law be clearer than that, if it is really decided on the merits? Don't you want those deciding your fate to to be answerable?
And yes, the country went through 160 years, solving slavery, polygamy, women's suffrage, etc. without the Lordship of the Supreme Court (Dred Scott was decided as a property rights issue).
Looking at just a few incidents from historically recent times you have FDR's packing of the court to overcome Legislative protection of the Constitution, the strange ruling on abortion (privacy trumps life), and most recently the Court's decision to uphold bans on political free speech, based on it being political.
Can't say I see the the USSC as a noble cut above Congress or the Executive.