Neutral Evil, by the definitions in the book, doesn't really contemplate ethics. The Neutral Evil character doesn't really debate ethics, they debate outcomes. They want what they want and they know how to get it.
Neutral Evil people are evil because they are selfish and see the world as an evil place. Why not do what you like?
Most well adjusted people look at evil characters with trepidation. Evil for the sake of evil is bad. However, when it comes to party dynamics, the Neutral Evil character seems to be the most stable. They are always up to the same old crap, only the prizes changing. What is interesting about this is they want stuff for themselves, they are not necessarily there to cause problems. Especially when a problem interferes with obtaining an objective.
The classic Neutral Evil move is to cause conflict in others. "Am I really going along with this?" Why, yes. You are. Neutral Evil characters are somewhat the core of the parties ethics. They see an objective, they get the objective. But by causing these ethical conundrums within the party, they do some arm twisting while also turning their own tactics on their head.
If a Neutral Evil character knew that they could have an amazing, priceless tool they would want to have it. If it meant donating a 100, 1,000 or even 10,000 gold pieces to a lawful good temple, they'd weigh the cost of killing everyone in their way, then fork over the money. Who cares if they just funded an orphanage, they got some great out of the bargain. Neutral Evil characters believe the world is evil, so backing a good cause is a meaningless thing to do because they believe it will end poorly. It's aligned with what they believe. They don't have to try to pay evil unto evil, because they really think everything is evil, all choices are selfish in the long run.
Neutral Evils are sort of suckers, while they imagine that everyone else is the fool. Within the group, they have a tendency of currying favor to get what they want. They might be the person healing every day or handing out potions of healing to make sure they, themselves, don't die. They might forego some immediate benefit because it serves the cause of getting something better later. And they tend to drag the party with them.
By picking the path of Neutral Evil, you have reduced your character's complexity and dropped that dynamic in someone else's lap. The paladin, ooo, he hates you for being right so often.
Remember, people want to believe things are relative. Sometimes they are not. You don't have to be some axe-crazed killer to be evil. You can be an affable, kind person with some really bad habits and goals. This is the role of Neutral Evil. They think, plot and plan to get the most out of any situation, which is oddly exactly what the rest of the party, regardless of alignment are probably doing.
