Who cares? The death-knell of many comic adaptations has been slavish attention to appearance and lore, but with no attention to characterisation and themes. And whether you're talking about a comic or a film, it's the characterisation and themes that make it worthwhile. Even within the comics, costumes, names and appearances change regularly - 'accuracy' on those details usually means meeting whatever image was presented in the last film, or the comics during the silver age, rather than the character's current depiction in the comics. How many 'die-hard fans' of the Batman film would rage if it had Dick Grayson as Batman (now that Bruce Wayne has been pwned by Darkseid and killed/stranded in prehistoric earth) and Bruce's son as Robin, as is the case in the current continuity?
The hero's costume, name, powers and origin shouldn't be automatically replicated. The writer and director should take into account that film and comics are very different media, and whilst modern audiences are a lot more familiar with the details of the comics than they were during the 80s, they're going to have to change some of the superficial details in order to preserve the themes. Some of the characters that are 'OMG-AWESOME' to many of the comic fans simply won't work in film. Bane and Doomsday are popular because they defeated Batman and Superman respectively, but they'd have no appeal as film characters. There is a reason why Bane has been awful in every film/TV version - forget about the 'OMG IN ONE OF THE COMICS HE WAS DRAWN BEATING BATMAN!!!' for a moment, and think about how he would work in a film script. He's a big strong guy, who thinks and is cunning...and stuff... - yep, in a film (where you need to show rather than tell) he's basically the most vanilla villain you could think of. Doomsday would be worse - all he can do is hit things, and that really doesn't make for a great film - you'd be better off watching a decent boxing match.
Moreover, neither character would convey any sense of a real threat. The audience already knows that the hero will fight the villain a few times. The audience also already knows that the villain will get the upper hand for a while, maybe even seriously wound the hero, but that when they fight at the end of the film the hero will win. Big-strong-punchy villains simply don't present any threat in a film - they're just there for the special effects guys to blow some money on and provide the audience a few minutes of visual spectacle to give them a 'time-out' from the plot. A film needs a villain that can be given complex characterisation - such as the Joker's embodiment of anarchy, where a major plot arc can be devoted to the question of what the hell motivates him. Punchy-villains like Bane and Doomsday can't corrupt the heroic D.A. into a fellow embodiment of chaos, they can't question the legitimacy of the hero's moral high ground, they can't drive a mystery for the plot to revolve around. If you want them to have the same 'threat' that they possess in the comics, you need to change them into something that be threatening on film, even if it means abandoning the superficial details.
Take three of the greatest mainstream comic adaptations of recent decades (I'm not including the more offbeat comics, like Sin City or the Crow, as they're a different genre entirely) - X-Men (1 and 2), and the Burton and the Nolan versions of Batman (Batman 1,2, Batman Begins, The Dark Knight). All of them changed the superficial details drastically. Especially the X-Men. The line-up of heroes is drastically altered, personalities are different, ages are massively different (e.g. Rogue as a teenager,Iceman, one of the original X-Men, a teenager, Wolverine in the same lineup as the first-gen characters, just for a start), and their powers are changed or limited. BUT it captured the THEMES - the Malcolm X v Martin Luther King symbolism, the notion of victims of racial hate struggling between pacifism and revolution, the sense of the characters as outsiders largely tormented by their 'powers' - that's what makes something a great adaptation. Not whether the costume looks like the one in the comics, or whether a guy shoots electricity instead of fire.