Yeah the Senate would be just lovely if only the career politicians in State legislatures got to elect Senators.
In 2010 the Tea Party movement took more gains in state legislatures than in Congress.
Voters before 1913 and the 17th Amendment knew their votes in state elections mattered to US Congressional elections and were thus more involved at the state level. The states thus reflected more the will of their voters; now it does not matter so much what the state does. Hence, states are irrelevant to national elections and and states rights have suffered as a result.
As it is now voters do not know their US Senators and large money interests are what elect US Senators.
With repeal of the 16th and 17th Amendments (the 18th is already repealed; all were passed in 1913 under Woodrow Wilson, an arrogant condescending academic from Princeton who knew better what the little people needed), with repeal the states would once again be relevant to US national elections and local politics would become much more important to state voters; as well as repeal of the 16th would constrain Congress to work with states to raise direct taxes, thereby drawing in more participation of voters at the state level.