Term Limits should be applied to members of congress to impose a 12-year service limit on members serving in either house.
The effect would be that Senators would only be electable twice, Representatives a total of six times, with time served in either house counting toward the 12-year limit (ergo 3 house terms and a senate term would disqualify the member from running for either house again).
Any and all current senators and representatives with over twelve years in congress would be prohibited from running again.