There is no such thing as disease resistence or immunity apart from undead and demons that are largely unaffected by it. You can feign "disease resistance" by giving tham a little regeneration or perhaps recuperation (but that would remove disease entirely) One idea could be to overwrite MA C'tis to gain the miasma dominion, and then give the "disease resistant" troops recuperation, they would get diseased and heal and get diseased again. This would not work with old age.
You cannot make the dominion affect luck scales, but you might be able to create a site in the capital that increases luck. You could also make a summon that brings luck events or increases luck scales where it resides.
I think it's a cool theme, but if you want more substantial feedback you better do some sprites and stuff to show first.
If you want technical advice on modding you'd be better off asking in this forum:
dom3mods
Re: Proposal Plague Lands
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