Because there is currently a term limit for the President of the United States (two terms - 8 years) there must be term limits on Representatives (6 terms - 12 years) and Senators (2 terms - 12 years).
Additionally, Congress (House and Senate) shall not vote themselves pay and benefits changes unless they are equal to those that are given to persons on Social Security, Military Pay, Retired Pay, and Medicare (COLA, etc.) as inacted by law.
No Representave or Senator shall receive retirement pay and benefits unless they serve 10 years.