Wait, why does an evil person care about the betterment of society besides how that betterment affects him?
I don't think he does...he's evil. I can see him supporting laws that benefit him, sure. Again, because he's evil. But what about laws that don't? Does he still support those? Or does he ignore them (even on the sly)? I can't see him supporting a rule of law that doesn't benefit him...he'd ignore it. Hence, NE.
Dr, Doom is not LE. He plays at honour, sure, but he'd throw it all away just to prove he was smarter than Richards. Or to gain power. Yeah, he repays debts to maintain an internally consistent self-image, but that's not enough, IMO, to be authentically LE.
Because a better society
by definition is better for him.
That's part of the definition of Lawful.
And yes, an LE person could support laws that don't benefit her, or even that are detrimental to her. She may pursue the power to remove, modify, or limit those laws, but she will still
respect those laws. Because legitimacy is fundamentally important.
Does that mean that she will
always support such laws? No. But that's not because she isn't LE. It's because LE has *exactly* the same fundamental problem as LG: having
two central values. Lawful Good characters have to ask themselves "do I adhere to the Law, even if it says to do not-Good things? Or do I do the Good things even though they are against the Law?" Does that mean that you cannot "authentically" play a Lawful Good character? I would say no. I think it's perfectly possible.
The LE person genuinely believes that the Law is
the best way to pursue Evil, and that Evil is the best (or at least the most natural) expression of the Law. Sometimes, though, the Law will require you to do things you don't like doing. What's the most stereotypical characteristic of a rigorously Lawful Evil villain?
Keeping a promise to the hero(es). Even when it costs them, even when they had hoped to find a legitimate means to get out of it--they keep the promise, because "they have standards" or "my word is my bond" or whatever.
So the real problem, I think, is that you're asserting that there can only be
one core value, which throws ALL "corner" alignments into being "incoherent," not just LE. I, on the other hand, am perfectly content with the concept of incommensurate but real and important values (I'm strongly persuaded by more modern versions of
virtue ethics, which postulates pretty much exactly that).