These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Author's Saving Throw: A Saving Throw based on something that happened before the series even started. Prior to the New 52 series beginning, DC announced an art contest based around drawing a page for the #0 issue that ended with a panel described in the script as a naked Harley about to commit an Electrified BathtubBath Suicide. This sparked Internet Backdraft over an apparent misogynistic eroticisation of a woman's suicide, made worse by the fact that the script didn't include any of the dialogue, or indicate that it was meant to be contextualised as a fantasy sequence. When the issue was published, the final panel of the page showed a fully-clothed (well, as much as she ever is in the New 52) Harley Riding the Bomb instead.
Broken Base: Harley's costume choice in recent years, primarily due to how Stripperific it is. On the one hand, a large group of people consider it rather sexist and exploitative, as well as not really fitting her character and being an unneeded change due to her costume already being rather sexy as it is, and so resent how her old costume is now going unused. On the other hand, the new stripperific look has became something of a Memetic Outfit for her, so obviously a lot of people feel different.
Periphery Demographic: Bizarrely, in the BDSM community, not only is she well-liked, her popularity VASTLY overshadows the Joker's. Not so bizarre when you remember that she's shown some kink tendencies of her own in the past, and her relationships with Joker, Deadshot, and Ivy do give way for a lot of Sub/Dom implications.