i myself am not the best writer, but i have read a grand number of books. The deamon man can be done right, if written like it is in first heretic, betrayer. or other well written posesion stories. Though it will allways make your carectar alot more powerfull (with some setbacks like pain from just being close to a grey knight). and the major lorse in humanity and selfcontrol. your carectar is much better than some of the previus editions, but he seems to allways be a bit cheesy/sueish. but that is how it often is with selfinsert fanchars.
What do you think would make a batter abhuman strain? Avian-like humanoids Barbaric stable beastman strain Technology worshipping munchkins or a slave race of xeno/human hybrids
Make me! I have no interest in making Ewoks or Ewok like beings! Xeno-Humans because they're the coolest. Even if they're are slaves because eventually the slaves with overthrow their rulers.