Shen Wei and Ye Zun having similar/mirrored powers – which, actually, come to think of it, makes me wonder if perhaps one of their parents might also have had a related power, if not necessarily a strong one ...

I love the two sets of identical twins, and the mirroring gives us possible insights into Nianzhi's share of the family power--he put himself inside the doll, became it, rather than animating it and fighting/killing with it. Nianzhi is nonviolent and inward (Chu Shuzhi describing him as shy and kind, etc.), Shuzhi is aggressive and outward.

I'd never even thought about the role a family/inherited power might have played with Shen Wei and Ye Zun's parents! That is fascinating to consider.