Since 1913 we have seen unchecked growth in central authority out of Washington, and the 17th admendment is one big feeder root of it. Is there a single senator any more who is responsible to the Constitution, who would hold any Federal agency responsible? Why should they? There is NOTHING in it for them to raise flack over a federal issue. If it is a established agency, it hardly gains them political headway to charge partisanly against that politically neutered bulwark, for no voter long beholds it for a party issue.
The States might check the Federal overgrowth, for the political sake of state politcians. But we no longer have even that check, and those who favored the 17th when ratified made their case that a state's legislative votes were more easily bought than the general electorate. The Oil Senators from oil states, the Coal Senators from Coal States, etc. At least they did represent their true state interests, and not just that of the beltway class.
The cancer-like over growth of Federal power has followed on that experiment -- it is a failed one, and needs repeal like was done with the 1919's sad 18th amendment, thankfully repealed in 1933's 21st amendment.
We think of FDR has the founder of the current federal socialism, that is not true -- the founding was in 1913 and therabout. FDR packed the Court, and finalized the socialist takeover, but it was the "progressive" tempers of the 1910s that set it all up.
The Civil Service Act should be repealed along with the 14th through 17th amendments. Of course, IMO, the list of what is ripe for repeal would probably be nearly impossible for me to complete in the time left to me.