One of the common complaints I'm coming across regarding this new "Justice League" DCAU production (other than the replacement of "Aquaman" with "Captain Marvel" who is now "officially" called "SHAZAM" -- but if you watch through the end credits you'll get your answer to why this animated feature chose not to carryover DC's resident "pet fish" this time around) has to do with the "unherolike" behavior of our beloved "SuperFriends" -- they're rude, they're obnoxious, they're backbiting, they're pouty, they're haughty & headstrong... they're just not very likable people. Well, I for one do not see any of this as a problem! In fact, I think this take on the "Justice League" makes for better story telling.
Keeping in mind that this feature is the first one based on DC's "New 52" storyline (unless one wishes to include "Flashpoint Paradox," which I personally do not), I do not see the characters' behaviors as being any sort of a major problem. Nerve grating? You bet! -- that is, *IF* you're any of the "over 20" crowd who has grown up on a steady diet of archetypal "honorable hero" vs. "unambiguous rogues & villiains" who play their respective (expected) roles: whether these are characters as portrayed in comic books, professional wrestling arenas, first-person shooter video games, etc.
So even though it was somewhat "unsettling" to observe these great heroic figures acting all cocky and/or behaving so immaturely with little or no refinement, this set-up actually works and plays out more realistically (though admittedly it's a bit "overdone" at times) once we take into consideration that (in this "new" reality) these are in fact "NEW" characters with "never before seen" abilities who have been thrown into a society "unprepared" for them and often "unreceptive" and "distrusting" of them -- in other words, the people (of the "New 52" universe) have yet to view and embrace these "aberrations" as "heroes," even when they do things that clearly are "heroic" in nature!
So it "feels right" that these "unique" individuals who are just "starting out" do not feel a need to behave "stoically" or with a mind of "responsibility" and "respect" toward the public at large or even toward one another, thus they have this air of "self-importance" about themselves -- or to quote it another way, "With great Power comes great Arrogance." These characters with their "special abilities" which nobody (not even the "supers" themselves) yet fully understands or respects are more-or-less acting on "impulse," much in the same way that any one of us who found ourselves endowed with a similar "special ability" or "fortuitous advantage" which had just been suddenly thrust upon us would/might fall susceptible (think your typical newly discovered "hot" film/television/radio "overnight sensations" who rapidly expect to receive "preferential treatment" in all aspects of their public lives, for example). These are characters who are still trying to make sense of their world and to find a way to fit/work in and around it -- in fact, the whole time I was watching things play out with them, one though kept haunting my mind: "These guys are just within a breath and a half of becoming the 'Crime Syndicate'!" (see "Justice League: Crisis on Two Earths" to get the reference)
So watching these individuals not only coming to terms with their "special abilities" but also trying to "manage" them in ways just enough to keep themselves from crossing over that fine line into the "dark side," as it were, it was refreshing to watch "heroes" *GROW* into their own, rather than just being "born honorable" or having an "epiphany" which makes them instantaneously "angelic": these are "good" people who recognize that what abilities they possess could easily "corrupt" them, but who are still working their way through these abilities trying to find their "true calling."
I was initially afraid that they were going to try to go the "X-Men" route by making the "New 52" characters the objects of blanket hatred by the masses (perhaps they can still go back to their archives and reintroduce "G. Gordon Godfrey / Glorious Godfrey" from the "Legends" mini-series and work that back in into the "N52" line, especially since they decided to introduce Darkseid so early on in the new history), but the fact that after having been objects of so much distrust, theses "costumed vigilantes" have actually shown themselves to be on "our side" and have thus not only won the respect & admiration of the masses, but the "costumed" warriors themselves have also come to appreciate and have more respect for what possessing those powers and abilities truly means to themselves and to others, and that these chains of events with regard to the repelled intergalactic invasion becomes the catalyst which finally begins to transform what are essentially a group of reckless kids in adult bodies (though still quite literally in Cap.Marvel's/SHAZAM's case) into the "heroes" we know we can expect them to become in time.