We have term limits, they are called elections. We want politicians that are seasoned, i.e., get better with experience. Term limits kill that possiblity.
The power of incumbancy makes it almost impossible for challengers to really mount an effective campaign.
I am in favor of strict term limits for congress. If the president is term limited, so should congress be, even if it requires an amendment.
The current hacks in congress, like McCain, Pelosi, Reid, Specter, Byrd, Kennedy, etc, really need to make way for new people in there.
The original intent was citizen legislators who would serve and go home. What we have now are hacks on both sides who do the bidding for everyone other than those who pay their salaries.