[Snake]

Could a few races get a certain trait that makes them immune/resistant to Poison damage, since their body doesn't really have the means to conduct it or they're naturally resistant to diseases and such? I'd suggest something like this:

>> Artificial Physique - A living puppet with no bodily fluids. Reduces all healing by 20%, but grants immunity to Poison damage.

This would go for Mechanations and Liches.

>> Vile Connoisseur - Your body was made for naturally consuming unhealthy things. Reduces HP/FP recovery and duration from food by 50%, but grants 30% Poison resistance.

This would go for Homunculi mainly, and maybe Vampires as it's stated in their lore that they tend to resist diseases better.

And beyond that. While this seems imbalanced in a sense, I'd prefer for players and monsters to get ways to bypass Poison immunity/resistance, than races that make sense to have those not get their cookies because we don't have the former. So! Future proofing for a few things too, maybe, sorta.