That's a good point about alignment GreyWord, 5e has moved very far from needing to bother about alignment, and all the other games I play or run have never needed to use it. That said, Planescape originates from 2e, and its very setting is based on alignment differences, and its cosmology is based on the Great Wheel, ie all the Outer Planes represent an alignment. So the setting is very much law vs chaos, good vs evil, but expressed through the various factions, and the choices a character often has to make might depend on their philosophical inclinations.
So even a faction such as the Mercykillers could comprise of both good and evil members, the good ones striving for merciful justice, the evil ones preferring retributive justice. That's the kind of dilemma this game will demand of its characters. If this sounds like something you'd enjoy or want to try, then I've got an open spot!