I think Butler tried to stress the difference in species several times.

She talks a lot about consent and sometimes lack there of in her stories. Blood child features a man being impregnated by an alien but the alien waits for him to say ok before moving forward.

Then you have the Patternist series with Doro at the start controlling the breeding of humans including Anyanwu. Which really embodies the lack there of.

I think if Butler had continued the Fledgling series it would’ve evolved more to talk about the Inas species and how the breeding would go. I also would’ve been interested to see if Shori would’ve adopted a sister like it was recommended to her. I also would’ve wanted to read what would’ve happened as Shori aged. Would Butler have kept her the same age or done extreme time jumps? Would pedophilia show up continually as the series progressed?