Congress should have mandatory term limits of 10 years.
As it stands now, Congressmen can serve for life as long as their constituents continue to reelect them! Once elected, an incumbent has a 90% chance of staying in office.
No term limits inhibits democracy by allowing Congress to gerrymander and redistrict. Also it inhibits Congress from getting anything done. They focus more on whatever false promises they have to make to constituents in order to get reelected instead of making laws that help America and her people.
Term limits would ensure that Congress made the best of their time in office and got done whatever needed to be done. New leadership and ideas every 10 years would ensure that America continues to change and get better.