Maybe a reason that made the whole Aeryn backstory /more centered eps easier on us compared to Zhan, D'Argo and company is because the Peacekeepers (hence Aeryn) look like any human would. To the mind's eye, we can relate more to them than we can the others... even if their ways is completely different then us, obviously. I don't know.

I will come back for a better comment, I love Farscape and I miss it totally and completely.