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.
Nicole's getting hate now because she's gone back to America to study, and never seems to be doing any actual studying. Netizens are resentful, saying she's quite average-looking, she "probably would have ended up working at a McDonald's in America", "she's not a celebrity anymore so stop writing articles about her"... Sheesh.
It seems like whoever gets added to the group to replace Nicole and Jiyoung will be subjected to this.
Tastes Like Diabetes: Honey, as the name would imply. It's more the concept than the actual song though.
Of course this is about the most subjective trope the tech demo evokes. Some people praise it for finally overcoming said valley, since Kara very closely resembles her voice actor and a real human in general (you can see the muscles move under her skin and her nostrils flare as she speaks). Other find that she still isn't human enough.