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.
Amanda Waller staring down Batman is probably the big one (loosely adapted into the Justice League Unlimited cartoon with Waller offhandedly calling him "rich boy"), but the gradual reveal of Oracle proved to be the one with the most disproportionate effect on the DCU.
For perspective, following her crippling, Barbara Gordon had been all but written out of the Bat-books and the DCU in general, and most people remembered her as Yvonne Craig in the Batman TV show from the 60s. After this, Oracle's become big enough to get her own TV show, several comic series, repeat Justice League memberships, and inspired the resurrection of a cheesy villain named the Calculator just to be her evil counterpart. She's generally considered one of the sexiest women in the DCU, and it's primarily for her personality and mind.
Deadshot. The series put the character on the map (he had less than a dozen pre-Squad appearances) and is largely credited for his popularity amongst fans. Because of this, he became the team's de facto field leader in the New 52 series.
The squad itself in appearances in other books. Virtually every time they've shown up in guest spots, it's someone's depiction of a "classic" line-up, leading to people hoping for a revival.
The guy's name is Captain Boomerang, for crying out loud, yet he's one of a handful of characters to survive the whole series while going on most every mission, even ones where his teammates actively try to kill him.
Tainted by the Preview: The New 52 reboot of Suicide Squad didn't make the best first impression. A lot of the people who would have eagerly supported such a book were put off by Secret Six getting cancelled seemingly to be replaced by the new Squad, and the new costumes (particularly for Harley Quinn) were... not well-received. Since the book officially launched, it has attracted a fair share of negative buzz for its gratuitous violence, characterizations that seem a bit off, and Amanda Waller's slimming-up.