I love the idea that Belinda could be the Rani. It is certainly a strong possibility, based on what we've seen so far.

I do disagree with you about the reveal of Ruby's mother. After all the hype pretty much any potential reveal would be anti-climatic. By choosing to make her merely human Davies at least managed to surprise the audience.

There is a fairly easy solution to this by having generic templates for commoner, cultist, tribal chief etc and then a mechanism to apply a racial skin. So goblin-commoner, bugbear-cultist etc.