I like term limits because it prevents people from making careers out of our free elections. Plus it prevents pork.
We have term limits here in California & it basically just means that many of the big career politicians just shuffle into some new office when they are term-limited out. Senatorial term limits would just mean that they'd go into some sort of state office after leaving the Senate to continue their career off of free elections.
Pork sucks, but let's not pretend that it is actually a meaningful drain on the taxpayer's pocketbook. Something like the Bridge to Nowhere is an easy target for everyone to beat up on, but even that carries an utterly miniscule price tag compared to something like Medicare.