Warner Bros’ fledgling DC extended universe (or DCEU for short) stands at something of a crossroads as Justice League prepares to hit cinemas. In one direction lies a return to the critical derision faced by last year’s Batman v Superman: Dawn of Justice and Suicide Squad, the disappointing opening twin gambits in this ambitious interconnected world of superheroes. In the other lies another dose of the redemption and sweet relief conjured up by Patty Jenkins’ heartfelt and intelligently cultivated Wonder Woman earlier this year.

So what can Justice League do to ensure this fourth and most important episode yet is remembered as the DCEU’s answer to The Avengers, rather than the nascent macro-saga’s ultimate nadir? Here are a few suggestions to ensure audiences leave multiplexes fired up with renewed belief in the future of DC film-making, rather than weeping at the prospect of dozens more movies yet to come.

Find a unique DC tone that doesn’t just steal from Marvel

From the looks of Jenkins’ Wonder Woman, the cure for all DC’s ills appeared to be surprisingly simple: add some charming character actors in the supporting roles, make sure the leads have a bit of chemistry, and most importantly throw in lots of Marvel-style observational meta-gags. But Dawn of Justice and Suicide Squad didn’t just fail due to a lack of comedy smarts; they failed due to muddled storytelling and spectacularly clumsy attempts at world-building. And because they were really quite boring, to boot.

Trailers for Justice League suggest that the film’s interplay between Batman, The Flash, Wonder Woman, Aquaman and Cyborg will be played heavily for laughs. And Warner Bros may be right to assume that comedy helps audiences to mentally paper over the preposterous cracks of superhero spectacle. After all, Joss Whedon, who has completed Justice League following the departure of Snyder for personal reasons, proved as much with his remarkably successful Avengers films for Marvel. But the new DC episode also needs to carve its own place in the superhero rubric. It cannot simply be a Marvel movie in all but name: these storied DC comic book titans surely deserve an essential tone of their very own.

Rehabilitate Ben Affleck’s Batman after his early struggles

Ben Affleck in Justice League. Photograph: YouTube

Building a comic book universe around Superman was always going to be a hard ask in 2017, as the occasionally one-note Man of Steel often registers lower on the decibel meter than some of his louder and more modern DC stablemates. So it makes a certain sort of sense that Affleck’s Batman is the guy putting a team together in Justice League. And yet the new caped crusader came across as a gun-toting Trumpian hothead with a penchant for punching women (before kissing them, natch) in his first two outings. There ought to be a moment in Justice League that addresses just how vile Batfleck was in Dawn of Justice and Suicide Squad, then some serious work on bringing him back to the light. Because if we don’t much like the boss man chief of this latest superhero ensemble, there is very little chance that we’ll warm to his colourful sidekicks.

Deliver a supervillain to stand with DC’s best

Ciarán Hinds, the actor behind the CGI Steppenwolf. Photograph: Johan Persson/PA

Marvel’s problem with supervillains is well documented. DC on the other hand, can point to Heath Ledger’s Joker as the greatest comic book movie bad guy in history, even if the clown prince of Gotham existed long before the DCEU was a twinkle in Warner Bros’ eye. In fact, most of the best villains historically feature in superhero movies based on DC properties: Terence Stamp’s Zod in Superman and Superman 2; Jack Nicholson’s version of The Joker, even Michael Shannon’s freakishly venomous version of Zod in Man of Steel.

Much of Marvel’s problem has been that digitally created alien baddies such as Thanos have simply not cut the mustard, and DC faces a similar issue with the all-CGI Steppenwolf, as portrayed by Ciarán Hinds in Justice League. Given that we live in an era in which the technical mo-cap miracles of the Planet of the Apes movies have become so commonplace that we hardly notice them, it rather beggars belief that comic book movies can’t get fantasy characters right. So let’s hope Darkseid’s giant lieutenant looks a whole lot more realistic than he does in the trailers.

Establish Ezra Miller as the only Flash that matters

Ezra Miller in Justice League. Photograph: YouTube

We’ve seen very little of Miller’s Barry Allen thus far, beyond trailers and micro-cameos in Dawn of Justice (during Batman’s “Knightmare” dream sequence) and Suicide Squad. There are those who feel that the role should have gone to the actor who plays The Flash on TV instead. But with respect to Grant Gustin, Miller has acting superpowers that are way beyond those of his small-screen counterpart, as evidenced by his creepy turns in Lynne Ramsay’s We Need to Talk About Kevin and much more recently, as conflicted “no-maj” Credence Barebone in JK Rowling’s charming and imaginative Harry Potter spin-off Fantastic Beasts and Where to Find Them.

From what we’ve seen so far, Miller’s Allen could be the ordinary Joe within this cavalcade of godlike meta-humans, a geeky, deeply green but vivacious and sparky addition to the Justice League team rather than the stale superhero of the CW show. Warner have hired themselves a class act to play the big-screen Flash, and it will take supremely turgid screenwriting to slow him down.

Give us a Superman we can finally believe in

Henry Cavill in Justice League. Photograph: YouTube

Everybody knows that Henry Cavill’s Kal-El is not really dead – the Man of Steel’s coffin wasn’t fizzing with energy all by itself at the end of Dawn of Justice. But getting Superman’s return right will be a key task for the movie’s sequel.

In part this is a matter of timing. Bring the big blue boy scout back too soon and he could easily overshadow Batman’s journey towards redemption. Take too long to restore the last son of Krypton to life and Warner risks releasing a second DCEU movie in a row in which its supposed biggest hitter barely registers. We learned nothing new about Superman in Dawn of Justice, beyond the pointless fact that his mom shares the same first name with Bruce Wayne’s long-dead mater. (Argh all over again at the memory of that cheap turning point in Snyder’s deeply frustrating movie.)

This time around, Superman has to prove why he’s always been the greatest superhero of them all. There have been moments of classy screenwriting in among the impenetrable mulch of the early DCEU movies, for example Russell Crowe/Jor-El’s clarion call to his son in the Fortress of Solitude in Man of Steel. “You will give the people of Earth an ideal to strive towards. They will race behind you, they will stumble, they will fall. But in time, they will join you in the sun, Kal. In time, you will help them accomplish wonders.” These are the lines that Superman now needs to start owning big time.

