Picard or Sisko.
Picard is one you can look up to. you know he is a seat of reason and judgement, and would be able to sus out a situation to a tee. He also gains respect by earning the trust of his crew.
Sisko is more no-nonsense and more aggressive than Picard, but he is fair in his judgments and has his crew's best interests at heart.
I'd want Picard in a diplomatic situation, or a situation that at first was difficult to figure out a solution. Sisko would be best to serve under in a military situation, or where the crew had to fight to get its way.