Skeletons should be magmaproof already, but the AI wont path through magma/water.
Tag for infertility is STERILE, which I already use. But they still marry, and its not a creature tag, its an interaction tag. It doesnt affect worldgen. All fort members have it, but worldgen creatures dont. I removed the child and baby tags from them completely, I hope thats enough.
Gem-free embark: Doesnt exist. Impossible. Without removing all gems from the raws you will never have an embark with no gems. I have genned thousands of worlds, never seen one with no gems.
I just added personality traits to the castes.
Ghouls are shy, angry, furious, untrusting cowards that like to hurt people, but have low selfconfidence.
Skeletons are super nice guys. They have strong sense of duty and friendlyness, altruism, helping others, high confidence and dont take breaks. They also have extreme love for art, nature and trust others completely. They are like curious, but naive kids. "I love nature and art, and want only to help" "Cut this tree in half" "ok, if you say so Master.
"
Warlocks are normal humans will all ranges of personalities, but generally distrustfull bastards that dont like to help anyone and think that they are better and smarter. Supreme Egomaniacs with a liking to intellectual discussions.
Are the fortress guard and royal guard sprites currently used for anything?
these are noble sprites. I can make unlimited of those. I have to check how it works with soldiers that serve in specific squads.
EDIT: seems that squad members that are lead by the law_enforcer (sheriff) get a different sprite then other soldier. I could possible make a squad for the mistress that looks different from the rest. Not sure what to use this for, because the members of the squad will still be skeletons, ghouls and mages. Maybe call them Inquisition or Jailors or Turnkey.