How about repeal of the 17th Amendment go back to what the Founding Fathers intended. Each senator speaks corporately for his state. Repealing the 17th restores a republican form of government. Today’s system just treats him as a long serving congresscritter-at-large by doing so it introduces the partisanship of the House into the Senate. The Founding Fathers system would introduce a tendency for a built-in cap in multiple Senate terms. Every state legislator & state grandee would see themselves in that chair. It might be modified by allowing the governor or any state legislator to introduce a bill of “no confidence” in the senator allowing a removal and a new appointee prior to the end of the 6-year term. Another small modification might be allowing the state legislature 30 days to appoint a senator failure to do so would mean the governor could appoint into serve for a year then the state legislature would have another opportunity to appoint.
Don't like your Senator? Elect new legislators to your state houses.
-PJ
Or the people can recall a Senator thru referendum.