I would go for a Hard Reboot of the DC Universe, basically the all-out version of what they're doing right now (incorporating Wildstorm and Vertigo, and making everyone a little younger). The Ultimate DCU, but rather than starting at day one, we're starting several years down the line. The world knows who Batman, Superman, Wonder Woman, the Green Lantern and The Flash are, but there has never been a Justice League, or a Justice Society.
THE POWER PLAYERS
1. The Daily Planet - Imagine The Huffington Post with the prestige and reach of the BBC... This is a world where the Press has made a phenomenal comeback. The Daily Planet operates as a 24/7 news network, as well as the most respected and well-read Digital Newspaper in the world. They have offices in every major city in almost every country on earth, and are dedicated to discovering the truth. The paper is funded by mysterious persons determined to ensure honest journalism across the globe. The Daily Planet hasn't been around for decades, It launched in the mid 2000s. As this new universe starts, the Metropolis team is moving into their new headquarters, a gorgeous, contemporary skyscraper that will define the Metropolis Skyline. Lois and Clark were new recruits when the organization opened its first Metropolis offices 5 years ago. The story that launched the organization through the roof was the first footage and interview with Superman. Vicki Vale works for the Gotham office, Iris West for Central City. The Planet has a presence in every title across the line.
2. Wayne Technologies, Inc. - Wayne Technologies created the first laptop in the DCU. It's well known that Wayne Tech is usually a good 5 years beyond what its competitors develop. Virtually every computer used by the military and intelligence services was built in a Wayne laboratory. The CEO of WayneTech is Jack Drake, a close childhood friend to Bruce Wayne. Unbeknownst to the shareholders, most of the cutting edge tech has been coming from his teenage son, Tim for the last few years. Bruce Wayne, majority shareholder, has been presumed dead for nearly a decade, when his charter plane crashed in the himalayas. Wayne is still beloved in his city, his father having been the most popular Mayor in Gotham City's history before he and his wife were shot and killed one night outside of a theater. The Waynes were the Kennedy's of Gotham.
3. LexCorp - Wayne Technologies doesn't make guns, LexCorp does. Lex Luthor is a self-made multi-billionaire who has revolutionized the way people kill each other. He also develops custom machinery to take down superpowered threats to the country. His pet project is developing and testing means to neutralize Superman. Luthor is well-liked in Metropolis for creating thousands of factory jobs in the 1990s, and his continuous philanthropy.
4. The Halo Corporation - Jack Marlowe is the first real competition to Wayne Technologies and LexCorps in years. They are in the business of making batteries that never run out. The dark side of the Halo Corporation is determined to conceal any and all traces of the two warring alien races determined to acquire earth as its stronghold: The Kherubim and the Daemonites. His team, the Wildcats, led by the mercenary known as Grifter, is determined to keep earth neutral in the war, and even more determined to keep the rest of the world aware that a war is happening.
5. The Green Lantern Corps - 5 years ago, Hal Jordan received the first power ring ever to land on earth. After proving himself to be a worthy Lantern, the Corps sent representatives to the US World Governments to sign a formal treaty placing Earth under the protection of the Corps. Before signing the deal, the UN negotiated that it would receive its own Green Lantern as a part of the agreement. The Corps representative agreed, and a second ring went out, ultimately choosing Guy Gardner. The Corps does not permit Gardner to act outside the jurisdiction of Earth, and most members of the corps find the idea of a government sanctioned lantern unsavory.
6. Stormwatch - The UN-Run Superhuman Black-Ops Peacekeeping Team. The organization is under fire after The Daily Planet revealed that Henry Bendix, the previous Weatherman, had authorized human experimentation with attempted copies of Batman and Superman, Codenames: Midnighter and Apollo. Bendix has been replaced with the head of MI:6 from London, Jenny Sparks. Rounding out the team is: John Constantine, Jack Hawksmoor, Guy Gardner (Green Lantern), Fire, and Ice. Jenny Sparks' liaison with the Secretary-General of the UN is Amanda Waller. The Secretary-General himself is Maxwell Lord.
7. The League of Shadows - The most dangerous terrorist organization on the planet. A powerful network of assassins led by a mysterious figure known only as The Demon's Head. Imagine the League of Assassins being boosted up to the level of HYDRA within the DCU, with the cooler name from the Nolan films. One of the head lieutenants of the organization is a figure known alternatively as Tao or The Demon's Tongue, a power broker with powerful abilities of manipulation
8. The Justice League - 100s of years ago, the psychic being known as Starro the Conqueror arrived on Mars, wiping out all but a handful of Martians before its defeat. The remaining Martians spent the following centuries focusing their considerable telepathic abilities to keep the creature dormant. However, when a transportation experiment went awry, and one of the last martians is beamed to earth, Starro manages to escape. It's hungry, and it's coming for earth. J'onn J'onnz, the last of the Martians, assembles a team of the most powerful beings on the planet to stop the advance of Starro. And thus, The Justice League is born. The League consists of Batman, Superman, Wonder Woman, Aquaman, Green Lantern (Hal), and The Flash.
Superman - Clark Kent spent his twenties traveling the world as an embedded reporter, helping when he could, but keeping a low profile. A few years ago, he was recruited by Perry White to join in on a new experiment in Journalism called The Daily Planet. When he arrived in Metropolis, he is inspired to start acting out of the shadows by the fearless Lois Lane.
Batman - Bruce Wayne faked his death when he went on his pilgrimage to become something more than himself… And when he returned to Gotham, he only revealed his presence to his best friend from childhood, Jack Drake, the CEO of Wayne Technologies. The Batman is a shadow that haunts Gotham, doing his best to keep it free of crime with the impeccable fighting skills he developed over the years he trained with the League of Shadows, and the advanced, experimental technology that is his birthright. Vicki Vale, reporter for the Planet, spots Bruce one night out of the costume, and starts investigating the truth surrounding his death, and what his connection is to the mysterious Batman.
Wonder Woman - Diana is a soldier of the Amazons, not their princess. She has been planted as a super hero, pretending to be just another metahuman, to gain the trust of the people and pass top secret military information on to her sisters to prepare for the war Themiscerya believes to be inevitable. She starts working against her sisters as she realizes that there is no need for war.
Green Lantern - Intergalactic Policeman with the most powerful weapon in the universe.
The Flash - The most media-friendly of the superheroes. I imagine his portrayal to be in line with the interpretation from the JLU animated series. He would be Barry Allen, but in name only.
Aquaman - Instead of making him king of Atlantis, let's make him Prince. I'd kinda like to turn him into the Thor of the DCU. Determined and moralistic, but with a sense of adventure. He'd be charming, and would not be anything like Namor in the least. No grumbling about landdwellers. He's curious about the world outside the water, and he's fun... Think the personality of a dolphin rather than that of a shark.
(Thinking this up was a whole lot of fun)