First, let me defend parties. Coming from a political climate that doesn't let parties grow, I've seen its disastrous consequences firsthand. Parties vet their candidates. They don't put their support behind a candidate which they don't know what he/she stands for. Result of having no prominent political party can be a president like Ahmadinejad. Nobody knew what his deal was. When he got to office, it was too late to change anything. Parties have platform. People can support the one with the platform they like and be sure that their elected representative doesn't stray a lot from their values.

As for the term limits, if you know you are going to be elected twice at most, what keeps you loyal to your party?