Since the question asks for favorite planet, and not planetary influence, I have to go with one that supports carbon-based life forms. That would be Earth, which isn't listed. Two other possibilities are Titan and Ganymede, satellites of Saturn and Jupiter respectively - but the viability is only theoretical at this point. Given protective equipment, able to withstand the heat of the Sun, I would still be crushed by its gravity. Same on the gas giants, Jupiter, Saturn, Uranus, and Neptune. Guess I'll have to go on appearance. Saturn is spectacular, and Jupiter is not far behind, but in a telescope, the shimmering blue-green of Neptune, with its subtle bands of color seems tempting. Knowing that there is carbon in the atmosphere in the form of tiny diamonds, clinches it. I choose Neptune.