I'm going to bring something up, and I don't know if it has, and don't really feel like reading 10 pages to check.
The concept of a Caste distinction is common not only in cultures throughout the world, but it's pretty universal among Indo-European cultures (yes, I know there's some controversy over whether or not the Vedic Religion and Vedic Sanskrit are Indo-European, but for the sake of my point, assume they are connected somehow). Among the Germanic Tribes, who were also Indo-European by the time the Romans wrote about them, there was a social order not unlike that of Varnashrama Dharma (which would become the modern Indian Caste System):
Thrall (slave) - Corresponds roughly with Sudra
Carl (freeman) - Corresponds roughly with Vaishya
Jarl (nobleman/King) - Corresponds roughly with Kshatria
I say roughly, because in whatever way the Vedic Civilization and Germanic Tribes were related, there are several thousand years separating both, allowing for plenty of divergent evolution. (Plus, the Germanic Tribes, unlike the Vedic Culture, weren't writing anything down).
There is kind of an equivalent to the modern Indian dalit, or untouchables, in the form of Outlaws. Now, this isn't being an Outlaw in the Robin Hood sense of woodland freedom. Being an Outlaw, whether temporarily or permanently, meant that you were ostracized from your village (a village that would have had technological sophistication on a similar level to that of the Merry Men's Sherwood camp), and anyone could kill you without fear of any repercussion. It's literally being Out of the Law: you may not have any obligation to follow the law, but neither are you under any of its protections. It would have been a terrible thing to be branded Outlaw, and to be branded one permanently might have been the worst thing.
Both Thralls and Outlaws were sometimes subject of human sacrificial rituals. A Thrall can serve the Gods like he served his human masters, and an Outlaw can bring some honor and good to the land in death where before he had none.
I probably don't need to say this, but just in case it's not clear, I DON'T hold to this conception of social stratification, either. I believe strongly in due process of law so that even the most heinous of criminals still have some legal protection(not for their sake, but for the sake of the falsely accused), and I believe strongly that all human beings have inherent worth and dignity beyond being simple tools: by default, everyone is free. And I've said it before, but I'll say it again here: I strongly, strongly believe that any form of ritual human sacrifice should stay in the past where it belongs.
However, there are some other big differences in this system as well that aren't as grim. A Sudra is a worker, and is equivalent to the modern conception of the Working Class. They are not slaves. Thralls are very much slaves: they are property, like horses and cattle. BUT, unlike in the modern Caste system, a thrall can potentially work their way to becoming a Freeman, so there is room for movement in the social order. There is one aspect of this system that I do believe in: when a Thrall becomes a Freeman, he is presented with the Tool and Symbol of the Freeman: a Sword. All Freemen carry swords, both as a right and duty. This is another point of difference from Varnashrama Dharma: while Carl and Vaishya are rough correspondents, that's only in terms of the stratification, not in terms of the roles they played. All Freemen, or rather, all Freefolk, carry Swords as Warriors. Indeed, the very word "Folk" has an etymological denotation, now lost from the modern word, of not just "people", but "host of warriors". To be a person was to be a warrior. The US Right to Bear Arms is a modern descendent of this conception.
So, what's my point in all this? The bulk of an ancient system may be incompatible with the modern world, but that doesn't mean all aspects of it should be discarded altogether. There's nothing wrong with farming the bits that are compatible with the times, and just discarding the rest. My use of "farming" is not an accident: a farmer does not discard the entire field just because even the bulk of it may have gone bad.