Well picking up the previous comments on undead, i also dont like the idea people say that they would be the ultimate army but get this.
1. If you get killed by undead so that you turn surly you wouldn't join the people who just killed you and then be expected to serve these people like a slave, I for one wouldnt and start attacking the undead.
2. If the undead started attacking someone surly they would be no match for someone at full health and has not limping problems eaither that or they can just run away easy solution.
3. In this game what would be there food sorce as humans have grain and livestock, orc have there worgs and stuff and elves use the forest. The undead would need brains and organs so the only viable option would be to eat them selves or have a human/orc/elf breeding program because im sure enough they cnt raid people all the time as more they kill more there are more mouths to feed, or they would just try to attack somewhere and be ahniliated by soilders. thus all dieing out