Villains and the theory of narrative.

[CoffeeGrunt]

The Stalin/chairman Mao equivalent in the communist tau empire. Maybe a cadre fireblade who hates other castes.

You clearly understand nothing about Tau fluff

All the chaos dudes who could potentially see chaos as the good guy- chaos will accept everyone; whatever race, caste, social status, etc. nurgle will save you from diseases. Tzeentch will take you for your intelligence, not your privilege/elitist breeding. Slaanesh... Well... Will sex everyone and everything.

That's how a lot of them see it anyway. Liberation from the lies of the Corpse Emperor.

the guard commander that is happy to win the war with a meat grinder of throwing hundreds of guard lives away for a win. A guard commander who killed his superiors to get promoted by filling dead mans boots.

You just described Commander Chenkov.

The Dark Eldar who just wants to keep his race alive and away from the clutches of chaos.

Asdrubael Vect? Only with more backstabbing...

A mathematician Necron who just wants to see what combat match ups work rather than win or kill everything. The fascination with escalating things to see what happens, and then boiling things down again to fill in his charts... necrons that see humanity as invaders on their tomb world and despoiling what they love rather than the POV of 'foul xenos'

I'm pretty sure Necrons have at least two eccentric general characters. Trazyn, for one, who simply attacks for amusement and to gain interesting trinkets, and that other one who's apparently short-sighted and very friendly to other races.

Marines that enjoy killing a bit too much.

Gabriel Seth?

Tbh, I think I would like a more warmachine style approach. More or less each faction in warmachine/hordes has characters that are the 'good guys' of their faction and the 'bad guys if their faction.

Then we can have no major events with everything being border scuffles, except Cryx who keep losing Warcasters, but don't because everyone just gets resurrected making any of them dying a pretty irrelevant story point. Fluff would devolve into Every Race Versus Nids if you did this to 40K. Menoth, Khador and Cygnar suddenly fighting together is a bit like Abaddon shaking hands with Stracken so they can go fight the Necrons together.

[Lurker]

That is true, I guess I brought it up to hint at it being a pointless exercise using contemporary standards, and in 40K standards, they are pretty good.

I suppose 40K-wise only the Tau and the Tyranids are not evil - and that depending on the levels of sentience of Hive Mind and whether or not you think Genestealer Covens and Zoats remain canon.

No it's a good point really. Having a moral framework to work with in an exercise like this is kinda necessary. I myself would equate it more to the Court Intrigues of Pre-Imperial China or the politics of late Imperial Rome. to an outside viewer everything that occurs appears to be one shade of evil or another. But when the viewer is part of it- then it's not "evil" it's just how you play the game. It's an intrigue on a galactic level, (which is just gonna exacerbate things )

For my money, I'd say the closest race that comes to not being evil (from a modern viewpoint) is the Orcs. They're like children (big hairy green angry children, but nonetheless...), they just don't know any better. However, from the framework of court drama, they're just as bad as anyone else because they play the game too, just in their own brutally 'act first' kind of way.

but as to the OP's original question? I got nothing, I can't even balance my checkbook and it's nowhere near as complicated as 40K.

[Fueldrop]

I'd kinda hazard a suggestion that the Eldar Exordites are fairly non-evil, being a bunch of Luddites who just want to be left alone and not have their souls eaten. They'll defend themselves, sure, but they're not out actively making life worse for the rest of the galaxy.
Ditto the vast majority of humanity, most of whom are just trying to get through the day, and probably the majority of the tau, who undoubtedly believe that the greater good is such a great philosophy that each sphere of expansion is simply the Ethereals allowing a new set of races to join the empire voluntarily.

The fact of the matter is that our entire lens of the universe is centered around a tabletop wargame, and as a result it's focused on conflict.

[Gamgee]

Tau are not even slightly communist. Tau are Anti-Communist. What Tau are is utilitarians. The Imperium of Man has more in common with Imperial Japan and Stalinism on a government level than the Tau do. The Tau rule over a federation of races who have joined. The Tau themselves are sort of like a republic. Then finally at the very top we have the philosopher-warrior king that solves disputed between castes and has a look at the larger picture (Ethereals). The Tau themselves are a strict caste system that would make Lenin pissed off that not everyone is equal. We have clear ranks.

Imperium is also as "weeaboo" as us. The fanbase draws their waifu SOB, they have a fascination with mecha, love of suicide kamikaze attacks, worship of a God Emperor (like Japan did in its past) and the Imperium is extremely Xenophobic the Tau aren't (Japan had to have its borders opened by gunboat diplomacy). The Tau only have an asian visual theme really.

Now how the **** does any of that sound like communism? It doesn't because it isn't. The closest thing the Tau have to a bad guy is Farsight because he follows his own path and made his own Enclaves, but even after being officially declared heretical by Tau standards there are a ton of them who see him as a hero.

[CoffeeGrunt]

Plus y'know, the Imperium's utter disgust for those who don't die in the Emperor's name and try to flee combat feels very similar to Imperial Japanese doctrine. However, it's not exclusive to them.

The Tau aren't Communist because not everyone is equal as you say, they have a clear ruling Caste. I think it's the American habit of calling anything that isn't a Capitalist Democracy Communism, ignoring differences in ideologies like, say, Socialism or Utilitarianism. Tau are not all treated equally, higher rank gains more responsibility, and the highest ranks of the Fire Caste get to actually retire. Your Shas'O can spend the last of their days sipping Tauquila on a beach somewhere after their hard work for the Greater Good. Many don't, as I understand it, but the option is there. That sort of reward system isn't Communist at all, not true Communist, at least.

The Tau have almost a meritocratic view. You'll never take leadership from the Ethereals, but you'll have their ear if you prove your worth. You'll gain rank and privileges up to and including piloting house-sized gundams the Empire only has in small, experimental quantities...at least in the fluff. Really it's only the Gundam-ish mecha look and the samurai-inspired Fire Warrior armour that makes them anywhere near Japanese-styled.