Depends really on your playing style. If you like Good because of its defence then go good. Most people will choose Neutral and Evil over Good though because the bonuses are just generally better. Some say that the defence bonuses of Good aren't nearly as good as the offence bonuses of Evil and that the unique buildings of Evil are far better than that of Good.

Along with quite a few others, I tend to go Neutral mainly because I like the bonuses (rush buying ships is cheaper I believe, all tile improvements are automatically done for free, best research buildings in the game), and I find that it suits my strategy best, and it makes you liked by Good, Neutral and Evil civilisations.

Each Ethic has its own suited victory too. Good suits Diplomatic Victories, Neutral for Tech Victories, Evil for Conquest Victories and all of them suit Influence Victories.

That is also true yes. Neutral is by far the best if you are going for a quick build up of your planets, which is why Xeno Ethics is a very decent tech to get early, and it also sells quite well to the AI if you use Tech Trading.