Career politicians are more susceptible to corruption by PACs and Lobbyists and special interest groups. Make the buying of our government harder by keeping a rotation of new people flowing through all branches of the government.
A suggestion: 12 yrs MAXIMUM in any one position
3 Four-year terms for Presidents
2 Six-year terms for Senators
6 Two-year terms for Representatives
1 Twelve-year term for Supreme Court Justices
A person could conceivably serve 48 years, but would have to do so by election or appointment to all three branches of the government.