When I was referring to "1 dimensional morality" and "2 dimensional ethics" I wasn't referring to morality in general being single faceted, but the specific type of black vs white spectrum morality (well, I guess now I put it that way, it really does become all morality as morality is the evaluation on whatever level of right and wrong, good and bad), and the 2 dimensional ethics is the one I discussed - D&D's cardinal alignment system. So I wasn't intending to say anything about morality or ethics in general, other than that those two specific systems are oversimplified. For example, the idea posed in the post following yours - that there could be a completely good or completely evil person (even though it is phrased as "few if any") boggles my mind in "what exactly does that mean?" Sure, people might agree to varying degrees that concern for the welfare of others is good. They might argue about how that is best obtained (let them get their needs on their own because helping them will only hurt them in the long run butterfly cocoon argument vs help those in need directly), but someone who has absolutely zero concern for the welfare of others may be seen as generally evil or sociopathic. But take the other side of the coin, "looking out for one's own best interest" is pure white to egoists and pitch black to altruists. And to the utilitarian, it's neither until acting on that is compared with the best interest of the population at large. What then, does it mean to be "pure good"?
So while any given population may have a majority consensus on some things that are considered "good" and "bad" because of unrecognized presuppositions acquired from indoctrination, those change over time and vary between different populations because of being rooted in indoctrination - what is valued and taught is different. The problem is when a game comes forward with a universal system of "good" vs "evil", and it conflict's with the player's own, it then becomes a "cramming down the throat" style of indoctrination. (In contrast, at least SW:TOR's light side vs dark side is a fictional creation, so if it doesn't match up with with your own notion of right and wrong, that's fine, because it's a fictionally creation about jedi behavior, not what is specifically right or wrong.) For example, the Sword of Truth series, the author wanted to be a modern fantasy Ayn Rand, preaching over and over the virtue of egoism, cramming it down the throat of the reader. The "good guys" were egoists, and the "bad guys" were abusing the concept of utilitarianism for an overlord's ultimately egoist desires. The "victims" were the people caught up with the bad guys trying to sacrifice their own needs for the needs of the many - utilitarians. To me, reading those books was almost torture, but I wanted to "see how the story ended" because the first book or two weren't really dogmatic, and I tend to like finishing series, although this specific series has had me reevaluate that.
So rather than subject players to a moral indoctrination, the choices should never be labeled objectively "good" or "evil" on either side of the development. People act toward specific values that they may use to create their concept of morality, but when the concept of morality is directly applied without thought of the underlying values, it's blind, and often only used as a means of manipulation to control others. Sure, let some manipulative self serving force say they're the good guys or that those they oppose are the bad guys, that's fine, it happens a lot, but I don't want to be evaluated by the game on what is "good" or "evil" as I have my own concepts and values.
Also, if it's written (the other side of development I mentioned above) with a standard of good and evil in mind instead of a value based system like the one I mentioned, it loses potential. My favorite example is the Song of Ice and Fire series by George R R Martin. There is "an evil" because it can't be communicated with and is hellbent on killing the living, but we don't know its motivations. The humans may try to be "good" people, or may not, or may change over what happens to them (Jaime). Tyrion tries to do good for the masses when he's hand in spite of what is said of him, yet he schemes and manipulates those in court (I suppose in order to avoid "pulling a Ned"). Joffrey might be called evil by some, or Theon, but they are just products of their environment and upbringing (and genetics). The child raised by a king with a HUGE sense of entitlement and a scheming, self serving Queen with an arrogant, overconfident biological father becomes king- how do you expect him to behave? People's love or hatred is based on stereotypes (the imp, the bastard), and their past perceived slights or benefits (starving in need of food, the other person made them feel embarrassed in front of an audience) more than any sense of specific morality. Granted, people loved Ned, but that was more of northman pride and years of good service and role in the war against the mad king than it was his sense of honor and tradition, and some only feigned support because of past slights between houses. The series hugely benefits by not clinging to some specific concept of morality or ethics.
Now I know a video game will never have an equivalent amount of writing to an entire book series, and that the writing done is choose your own adventure style reactive. But the more options that are considered and written in, the more sense of freedom people have in the game. Writing to values (serve yourself - seek profit, fame, boons, revenge; serve the people at large - just the locals, the nation, all nations, all races; serve those who have done unto you - reward, repayment; revenge - for percieved slights, for being manipulated, for betrayal, for your family/race/all the innocents) allow for more options than writing to black and white or side vs side. To me, Skyrim was terribly written - 2 opposing factions you can avoid but not leave untouched (empire vs stormcloak) and two opposing factions that one forces you to be with or against (blades vs greybeards), and you can't even kill the blades at the end to prevent their jihad which would likely spark a future dragon war. I tried playing a "for the people" type hero, and the writing simply did not let me uphold that. I either had to side for the war (which I was avoiding because it would hurt the people in general), or allow a family that utilized murderers to keep their family hold to power become a ruler of that town. At the peace talk table, I should have been able to bring up the corruption of the Silverblood family and insist they name another leader, or at least been able to kill the whole corrupt family off, but no, their jarl plant was "essential". Skyrim's choices are grey, but they are so few, it is still shallow even though it avoids black and white.