Those are all good questions. But I don't have answers to them. :-(

"Improving Society" is relative to each region. I guess it would be relative to the society itself. A bad example is watching a show similar to "Survivor" or "Big Brother". the competitors definition of improving society would be extremely different from the societal norms on Wall St.

If a group in California,USA defined societal norms and a group in Rome, Italy defined societal norms, would they be different? There is no correct answer.

I agree with your point

If the person is motivated only by money, then he is not able to improve the society.

What I was trying to steer away from was the idea that if you were to take a given political role, you will have a guaranteed salary. If the salary can somehow be controlled by the satisfaction of the constituents, that "might" improve things.