No, you're not muddying the waters. That's in fact what inspired the panel: how someone who was new to the fandom was introduced to it by being rec'd AUs, wasn't keen to read them, and ended up loving a lot of them. It happened to me as well.

You've named several of my favorite AUs, and I think that Harlequin Airs works particularly well, like Suitable Gravity, because there's the edge of danger in the story: the enemies, yes, but also the environment itself (trapeze act, no-oxygen surrounding). The grittiness of London, with its inherent dangers is something we tend not to focus on in the show, but it's that built-in threat that makes those two AUs my favorites as well.