okay ... then I will be happy to reject this idea IF!!! there will be the occasional tribe of lizardmen hidden in a cave of some-sort (same goes for centaurs and minotaurs) .... and occasionally a small pack of isolated wyverns living in a secluded valley ... to either kill or capture and tame. (perhaps some treasures nearby)
I suppose what I mean to say is ... I would like for living dungeons to not only be "places to kill stuff and get exp" but possibly places to make diplomacy with the inhabitants, perhaps limited trade (items, ect), and perhaps hiring mercenaries (what If I want to build a metropolis where humans, lizardman, centaurs, and minotaurs can live? Perhaps I can build a Lizzie ghetto, Centaur ghetto, Minotaur ghetto- with their own locations/population counts, and I can recruit from such population to get such units) Alternatively you could some-how keep track of what percentage of population is centaurs/lizardmen, and have a % chance equal to their percentage in the population, for each soldier made to be one of them .... with whatever weapon and items the other soldier would of had, but simply no armor (if they are not able to wear the armor).
I'd just like to have some limited interaction with this minor semi-human tribes scattered throughout, in some way, up to hiring for mercenaries or bringing them to my city to live. Of course, there is always the choice to kill them for exp and such ... and while this could net the most gold and magical items, you would perhaps lose your chance to interact with that race. (minor race as it may be)
same goes for a wild pack of wyverns, nightmares, lesser-drakes, or Rhinocerouses, Boars, or Lava-Salamanders .... these might not be intelligent enough to interact with on a civilized level, but such animals could be tamed into being mounts ready for warfare (of course, these such mounts would be rare finds in the Wilderness and, other than the Rhino, incredibly hard to tame "so you might see Rhino riders several times in 5 games, but a regiment of Wyvern riders only once")