I do Like the fact that you can breed humans with beastkins to get halfkins. Nothing make's breeding more Heart warming than to know half your gene's are in the offspring... ahem... anyway
i think the human, and beastkin > halfkin is really nice.
Viewing post in Modding - Races (Semi-official)
There's something in the games 'lore' about Halfkins having a the full beastkin gene that can come out. So any halfkin mother could have a beastkin child... with any race as the father. I'm not sure it functions this way in game. But it would be interesting to have a new halfkin race, which had a powerful beastkin variant that could only be obtained through breeding.
Or hell, just do it with dragonkin. Give them a chance to give birth to full on dragons!