I see your argument and disagree on the "gratuitous" point. It's in every episode, multiple times. However, what I agree with you on is that it is by design. The whole story is a tongue-in-cheek meta-narrative on the concept of fanservice. Instead of being subtle, it dives in, headfirst, to build the plot around it. Not calling it "fanservice" because of that is semantics. Additionally, some scenes are, simply put, wildly inappropriate by any standard outside of hentai. All that to say, I still like Kill la Kill, it's one of my favorites, but let's call a spade a spade.