I really like the idea of this thread. Soon I'll do a Marvel OYL, but for now, I'll detail what I'd do with DC One Year Later. With a few exceptions, assume the events of 52 went down the same way. Rather than doing the WWIII books, I would have had a series of annuals over the course of 52 for all or most of the current DC books, with each one detailing a part or sum of the character's journey during the missing year.
After the Crisis, Lois Lane decides to journey to Bialya. In the midst of Infinite Crisis, a particularly messy coup was staged, and Lois embarks to investigate rumors of genocide. Powerless, Clark decides to go with his wife, figuring he can do more help there than in the city, and hoping to support Lois. What they uncover is a whole series of political overthrows stretching through the whole region and into North Africa, orchestrated by Intergang. Bialya is their temple-nation, performing bizarre experiments and massive ritual sacrifices on the people. Clark and Lois get caught in the war-zone of World War III, and Clark is seriously injured. We'd pick up with a one or two shot of Clark in critical condition in a Middle Eastern hospital. Internally, he struggles with the duality of living his life like a human, but not being human at all. Slowly, unconsciously, his powers crawl back as the terrified and hopeless speech from the post-war wreckage seeps into his ears. He rises from his hospital bed and flies off to help with the disaster aid. Action Comics would focus on Superman's fight against Intergang both in Metropolis and abroad, with Darkseid as the long-term looming antagonist, Jimmy Olsen as a major supporting character (He'd replace Clark throughout the Clark-in-Metropolis 52 scenes) and the New Gods making frequent appearances. Superman would have Superman facing his traditional colorful enemies, particularly Luthor, who keeps a few loyal members of the Everyman Project along as his personal muscle.
During the one year gap, Clark left Kara behind as the official custodian of Metropolis. Deciding she needs a way to connect with the real world, he sets her up with an internship at the Daily Planet. Her annual would follow the course of a day as she tries to juggle all the different responsibilities Superman would normally have to face. OYL, she's like the Robin of Metropolis, cutting her teeth on crime fighting while dealing with the trauma of being a teenager.
Batman spent the missing year trying to get the monkey off of his back. The annual would deal with his journey to enlightenment. He realizes that the devil inside him cannot be destroyed but must be used as a tool, that he can be both The Man Who Is A Demon and The Demon Who Is A Man. OYL, Batman is believed to be dead. The bat-signal is still out of commission, and when the Justice League reforms (check that out below), their official pronouncement is that Batman won't be returning. Still, crooks and lunatics murmur about a ghost bat that serves as a spirit of vengeance. Some hypothesize a new person may have taken the mantle, while everyone who glimpses the Bat declares he's an avenging spirit, a devil of vengeance. The Batman remains an enigma, thought even by the police to be dead, while Bruce Wayne is the father-figure and philanthropist playboy with a heart of gold. Detective Comics would tell more noir-style detective stories, with the Gotham branch of Intergang and their connections to Ra's Al-Ghul and the League of Assassins as a slowly building threat. Batman would deal more with the traditional rogue's gallery.
Nightwing would have Dick Grayson in Bludhaven, trying to rebuild while preventing the criminal element from gaining control. It would deal more with non-powered criminals and threats such as the mafia and corrupt politicians, with the Huntress and now-legit Penguin (sorta) in supporting roles.
Robin doesn't need much changing.
I'd launch a new Question series, with a strongly noir feel. Montoya and Bulloch operate a PI agency out of Gotham City. Montoya dons the Question costume when necessary (and Bulloch would know the secret). The cast of Gotham Central would feature prominently, with Batwoman as the agency's enforcer and Crispus Allen as the Spectre making cameo appearances. The Kane family would be revealed to have strong ties to the remnants of Intergang left in the city.
OYL, Wonder Woman is the good-will ambassador for New Themyscira. She spent the missing year going on a pilgrimage to the seven mythic holy grounds of the Amazons. During the year away, Donna Troy has prophetic dreams from the now-missing Queen Hippolyte telling her that some amazons remain on earth, and that she needs to gather them together along with other strong women to form a new seat of knowledge and culture. Wonder Woman goes on adventures in the name of peace, while Donna tends to the difficulties of maintaining her new utopia.
Justice League of America would rise out of the three heroes' return, in much the same way they are now. The cast would probably be pretty similar to Dwayne McDuffie's, with the iconic characters taking the seats of prominence. Wally West would be the team's Flash, with Hal Jordan as the team's Lantern.
Justice Society of America would stay pretty much the same.
OYL, I'd have the three big guys gather together and decide that the superhero community needs more structure, and each of them coopts or forms a new team, each in their own vision.
The Outsiders are on the run from governments around the world after countless violations of international treaty. Batman comes to them and offers them a new direction: a black ops strike force which is known only to exist by the JSA and JLA. It is their job to work as an international metahuman secret police force. Nightwing would be in charge.
New Titans would be gathered together by Wonder Woman from the older members of the Titans (Donna, Cyborg, Beast Boy, Raven, Starfire, Jericho) to serve as a sort of non-partisan emergency services team. They face against mythic threats and as a search-and-rescue squad.
Infinity, Inc. would be formed by Superman and led by Steel, as a sort of support group looking to help rehabilitate delinquent metahumans and help new metas control their powers.
The Teen Titans would move back to an all-teen cast.
Hawkgirl would transform into a sort of modern pulp adventure series, with Keira traveling to the most exotic places in the world in search of powerful and dangerous artifacts which were scattered around the globe in the Crisis.
Shazam! would have Mary Marvel take over as the new Captain Marvel, with Billy as the Wizard Shazam. She'd be the sunny and innocent protector of Fawcett City, a town where magic and wonder run wild.
The Flash would have Bart, Barry, and Wally returning from the Speed Zone and settling back into the world. It would follow the whole family of Flashes, with Jay Garrick based out of Central City, Wally as the Flash and Bart as Impulse, in Keystone City. Barry would be retired, offering advice to both Bart and Wally.
I'd introduce another new book dealing with the international politics of the DCU: from Atom Smasher, who decided he couldn't abandon the people of Khandahq and took charge as their leader, to the nations under the sway of Intergang, to the Great Ten (with China having ceded Oolong Island to Bialya in return for metahuman research technology), and Bane.