Sounds sort of Exalted-ish, where the pinnacles of sacred/goodliness/godliness on earth were great examples of their chosen sphere. Some of them were not very "good" but they were revered nonetheless... they're perception as being "evil" (or their sort of "descendants/incarnations") has really little to do with their acts so much as the downfall of the golden era by their hands. The loss of all the knowledge, power, ability and prosperity seems more of a condemnation than the slaying of entire populations.
Generally I have [good] and [evil] as celestial paradigms dealing with alliances and affiliations, whereas "good" and "evil" are an entirely separate kettle of fish.
So, yes, excellence would make you [good] or [evil] depending on who sponsored/encouraged you, but you could still be "good" [evil] (tyrant who helps his subjects because prosperity makes him more powerful personally and less likely to be opposed) or "evil" [good] (zealot who slaughters entire towns because of their "taint", down to the children).
Generally I'm not a favor of static alignments anyways, so alignment descriptors are more resonance based on whose side you're most aligned with. In the larger cosmic ideal, it might as well be [ team red] vs. [team blue].
On an individual level.....it's all dependent on your deities ideals and the deific ideals of those around you as to whether you are "good" or "evil". A pacifistic god would see any warrior as evil, even the defenders-since they are violent and shed blood, whereas a god of warrior ideals would see pacifists as evil since they allow innocents to be slaughtered.
Yeah... it gets complicated. That's why we reserve detect alignment for mostly auras and supernatural entities. That and it's really hard for a DM to know whether the motivations of a character were noble or not, since few tend to explain their actions to the DM.