There's a perspective from which FDR's attempt to pack the court did work: He didn't expand the court, but the credible threat that he would do so got the justices to back off on blocking the New Deal policies he was implementing.

unfortunately with the way case law works, we are stuck with those bad decisions today.

> what we really need for SCOTUS is time limits and automatic replacements at intervals to take politics out of the process a little bit

Wouldn't the need for periodically choose replacements add politics instead?

We already periodically replace them, that period just happens to be their lifetime. If you shorten that period you lower the stakes if the "other side" gets to fill a slot, you'll get another chance to rebalance in X years, where X is a known value and doesn't require someone to die (or willingly relinquish power).

I'd rather replace one justice every 4 year term and occasionally one retires or dies than never know when they come.