I am not as worried about the prospect of a conservative Supreme Court for the same reasons as most progressives.
Now, I think that lessening the protections of Roe v. Wade will be a disaster for poor women living in red states. I also think that decisions weakening worker rights and collective bargaining will be bad for people in the lower half of the income distribution. And I think that weakening the ability of regulatory agencies to do their jobs will worsen life for many while providing few benefits: the Administrative Procedures Act of 1946 plus the Regulatory Flexibility Act of 1980 and Congressional Review Act of 1996 provide plenty of checks on their power.
And a new conservative court is going to make it harder to get an abortion, harder to join a union, and harder to regulate the economy.
That said, political action can cancel out adverse judicial decisions in all of the above. The only way a conservative SCOTUS could block a political counterreaction would be take us all the way back to Lochner v. New York. And that seems unlikely.
But it looks like a conservative SCOTUS will play hardball on gerrymandering and voting rights. They have already shown it. And they will play hardball on executive action. John Roberts will try to limit any outright partisan favoritism, but just wait until RBG leaves the court with a Republican president in office.
A partisan Supreme Court willing to put its finger on the election scales, well, that is a threat. I am not sure that it is a threat the Founders ever considered, but there are a lot of political developments that they did not consider. Hell, they thought they had designed a system that would prevent political parties and then they themselves went right out and built the Federalists and Republicans.
The “good” thing about the Kavanaugh hearings, I suppose, is that SCOTUS decisions will now be watched closely by the public. But I view a Court that is both biased towards property and against voting rights with trepidation.
So, what changes to prevent a purely partisan SCOTUS? Well, there is a proposal for staggered terms. There are also some more off-the-wall reform proposals. Mine would stick with life terms, but with a Congressional supermajority requirement and a clause automatically appointing a caretaker Justice chosen by a professional panel of Congress cannot agree. But none are likely to happen with our clunky amendment procedure. I fear that they will not happen before we see a far more serious breakdown.