The real problem with AD&D alignments is that they try to impose a simplistic mold onto very complicated sets of morality. And that's just the Good/Evil scale. The Law/Chaos bit was made by Arneson completely out of whole cloth, only for D&D, which is why so many people have such difficulty portraying it.
It is made harder by the fact that AD&D PCs are, to just about every culture other than their own, pure evil. Their entire existence revolves around invading foreign lands, stealing from somebody else (treasure out of chests, houses, bags, and whatever else isn't nailed down), and if anyone gets upset at this trespassing, massacring and looting entire villages of sentients - largely because they are not the exact same species as the PC-approved ones.
In fact, this was why the AD&D morality system was invented - so as to disguise the basic immorality of normal game play. Place the magic marker of "evil monster" on something, and suddenly traveling to their home to massacre and loot them becomes okay. And this made the game tremendously popular, because teenage-DMs did not have to think too hard: just set up monsters to attack, completely inappropriate loot for them to drop ('inside the belly of the giant snake, you find five readable scrolls'), and you're done. Hey, I just rolled a wondering monster!
However, as happened with Avlis's Starving-Humans vs Invaded-Elves, more complicated situations where both sides feel they're in the right always feel far more realistic, and thus more compelling. That's why all other RPGs of the same era eschewed overarching alignment. Runequest's Glorantha was largely Romanesque Moon Worshippers vs Germanesque Barbarians, as its main set piece, with no one being purely good. Tekumel was a fantasy Indonesian setting where all magicians largely got their power from making bargains with demon lords. Call of Cthluhu did have evil - but evil always won in that game; PCs were lucky to just survive. Paranoia was "evil as black comedy".
So the unrealistic simplicity of AD&D may be easier, but it will always lead to "alignment confusion", because the concept that "I'm 100% good, this killing I do is only what I have to do" is almost always a hallmark of someone who is deeply deeply evil.
My fame, if Providence preserves my life, will consist in ... works of peace, which I still intend to create. But I think that if Providence has already disposed that I can do what must be done according to the inscrutable will of the Providence, then I can at least just ask Providence to entrust to me the burden of this war, to load it on me. I will beat it! I will shrink from no responsibility; in every hour which ... I will take this burden upon me. I will bear every responsibility, just as I have always borne them... Thus the home-front need not be warned, and the prayer of this priest of the devil, the wish that Europe may be punished with Bolshevism, will not be fulfilled, but rather that the prayer may be fulfilled: "Lord God, give us the strength that we may retain our liberty for our children and our children's children, not only for ourselves but also for the other peoples of Europe, for this is a war which we all wage, this time, not for our German people alone, it is a war for all of Europe and with it, in the long run, for all of mankind.
~Adolph Hitler
I could not play Andy in the quoted 4e system... None of those fit her, really, maybe "good" at best, but it doesn't describe her (wildly selfish and fearful) motivations at all!