Adding experience isn't bad, although just generally more powerful units are kinda boring also. It could be more like the merchant ability with a couple less powerful abilities. Maybe slightly cheaper units that have slightly more combat strength combined with a unique ability that isn't too powerful.

Militarist is weird, I mean "levying population" makes a lof of sense and it's really enjoyable to push a button and spawn a squad. But spawning the generic militia looks ... weak and not sexy at all?

Only with OpenDev, I can't really understand what is the exact purpose of militarist ability.

- Grinding Militarist Era Stars on Independant armies and animals ?

- Pushing Violent Inpendant armies out of our territories ?

- Counter-attack ?

- Taking undefended outposts ?

- Cleaning lairs and sanctuaries ?

Seems to have a lot of potential, but maybe I'm just not convinced by the unit itself ?

Even in term of immersion, I don't feel than spawning a gang of peasants with a club really fit with militarist Huns for exemple. So I like the substance, not the form.

If the militia was a little more sexy, in term of aesthetic and artwork, and a bit buffed, maybe it will be already more attractive ?

When we didn't know what the affinity was doing, we could still argue in a rethoric way "this culture is militarist because...singular military doctrine...or whatever". But now, in term of gameplay, it don't have so much sense for some of the militarist cultures, in my humble opinion.

Again with the exemple with Huns, their singular nomadic gameplay, their strong unit, I don't understand what affinity brings to them, what is the synergy with these militia. I don't even think they need it. Is this affinity a sort of nerf because the overall design of militarist cultures is already too strong ? I don't know, but this affinity is definitly the less sexy of the roster :p

For a bonus related to moral, I can't imagine something too much interwined. It make sense, but it will limit the possibilities in legacy trait. For exemple the Hittite one is already related to moral. Same with unit experience, with the Mycenean Legacy trait.
The only idea than I can imagine is a small reduction in moral loss when a militaristic culture loses a battle . So it goes hand in hand with the idea of being motivated to go to war.

Finally, the affinity I like the least : Builder. Simply because very basic, no gimmicks, and not gamey. It's just about converting yields into production.

It's definitely very strong, but it's not appealing, or fun.

(shared project on wonders exclusive for builders ? being able to build a wonder reclaimed before someone else when builder ? ...)