I had a few ideas in my head but they were  mostly passing thoughts with no clear structure yet. But I do have a  more solid outline of how I want to see Dick Grayson used.
Nightwing
Basically I would have Dick be in a recon of Bludhaven that changed the  city to a more Atlantic City/Bludhaven type of place. Mirroring the  diffrence between him and Bruce, Gotham would be all dark and gothic  whilst Bludhaven would be all flashy, colorful and neon-lit. It should  have the best casinos, nightclubs, hotels, brothels (eh, why not?). I'd  also have it have the largest airport and train station where many stop  overs are put in place. 
Dick's day job would be as managing director of Wayne Hotels (allowing  him to travel abroad when necessary) giving the media a cover of Grayson  being a bit of privileged yahoo who's never sure of what he's doing.  Since he's never had a steady job and only rose because he was Bruce  Wayne's ward it would cause hostility towards him from his employees  (when ironically Dick is doing a fine job running the company). You  could also have a lot of comical scenes with Dick, the adrenaline junkie  that he is- constantly wanting to get out of work and get on with his  main job as Nightwing. 
   
As Nightwing though Dick would be closely linked with the rest of the  Bat-Family keeping an eye on the crime scene of Bludhaven (which would,  of course have strong ties to Gotham's). The villains would need to  reflect the city so you could basically have every gambling themed  villain (except Joker) in the DC Universe; Roulette, The Royal Flush  Gang or the more gimmicky colorful criminals like the Circus of the  Strange, Flamengo, Professor Pyg and even Kite-Man and Crazy Quilt  (illegally run tourist attractions run by small time crime lords) and of  course, a guest appearance from the Riddler. 
The criminal element would be a kind of super-villain Oceans' Eleven  with the trippiness of Fear and Loathing. A LOT of corporate espionage  and gathering place for various crime lords with villains always meeting  up in secret to discuss plans on a global scale. Since I'd like Oracle  (yeah that's right, **** nu52 Batgirl) to be ***** main contact in the  Bat Family in this series , I'd have the Calculator also have a major  role, linking the various crime organizations. The irony being that  while Bludhaven doesn't have that much petty crime (well, compared to  Gotham) it's actually the center of organized crime for the entire  country or even the world. Of course we'd still have the occasional sick  freaks who do it for fun (like Pyg).
		
		
	 
I love that idea.  I think DC should get on that right now.
You know  how cities go through reconstructions some times, Las Vegas did it a few  years ago.  San Diego is planning to do that in the near future.  Maybe  Bludhaven can do that in the comics.  You could have a period of  construction, where Nightwing is fighting crime in Bludhaven while  buildings are being evacuated, torn down, rebuilt, added onto, etc.  The  backgrounds, for a short time, could be construction areas with gates  up to keep people away, unfinished buildings with plastic sheets  covering parts, and piles of material.
And then, after a month or two of comics featuring that, Nightwing comics presents the new Bludhaven.  Your idea.
I love how your version of Bludhaven is brighter but still as crime ridden as Gotham.  
These  ideas about the city, his job, and the criminals would make Nightwing  comics rival any popular characters' comics right now I think.  And give  him a nice group of supporting characters too.  The regulars, like how  Spider-Man had Aunt May, Jameson, Robby, MJ, Harry, etc.  Dick can have  people who work in the hotel, etc.
Again, really great idea.
Here are some of my ideas:
In the past 
Donna Troy  found out that she was actually a Titan God who was sent to Earth,  hidden with the humans, to teach her to be a better titan god.   Ultimately she gave it all up to be a normal human, to be a mortal  version of Wonder Girl.
But in the New 52 I think she should return, as the Titan God brought to Earth.
Her  story would be similar to Thor's or Hercules.  She is a demi god, with  incredible strength and power.  She is sent to Earth to live among the  humans on Themiscara, and to be trained by Wonder Woman and the other  Amazons, to teach her how to be a hero and a warrior.  Like Thor or  Hercules it would be like a god walking among men and women, sort of out  of place and awe inspiring.  But she could still be the same Donna Troy  she was in the comics, just with a newish origin and powers.
		
		
	
	
I would also have a comic starring 
Booster Gold, like before the New 52, and also starring 
Rip Hunter and the 
Hour Man android, and 
Booster's sister.  And 
Booster's great grandmother who is currently a 10 year old girl  who he saved from a distant horrific future.  It would be a comic that  takes place outside of time and space.  Almost like the Exiles.  It  wouldn't effect the regular DC universe unless certain stories took  place there like maybe having to save the Flash or something.  I would have each of them remember life before the New 52, the altering of time didn't effect them.  But they understand (except maybe Booster) why they have to just go along with the change and that this is the timeline now.  Things changed but they cannot change them back.  But that would allow them to talk about the New 52 and about how the stuff that happened before did happen, but then the New 52 Happened and stuff is different now.  Sort of Pre 52 and Post 52.  Superman and Lois were married, but now they aren't.  Etc.  This comic could also help readers except the changes and let them know what is the same, what is different, and that the stuff they loved before the New 52 still happened.
The team would also deal with a lot of Time Travelling stuff, like Chronos, Captain Atom, WILDcats Void, Warp, Pandora, etc.
It  might also be really really cool to bring Ted Kord back in that comic,  but make it that he cannot return to the regular timeline.  So he has to  stick with Booster and his time team and stay out of the regular  timeline of the New 52.
I would show that because of the New 52 
Max Lord  used his mind powers to erase everyone's memory of himself and Ted Kord  or the JLI ever existing so that no one would remember he was ever  alive, or that he started the JLI, or that he killed Ted or took control  of Superman or was killed by Wonder Woman.
The only person who would  remember could be Booster and he only remembers Ted Kord, not that he  was Blue Beetle maybe.  Just that they were friends.
Or maybe bring back 
Ted Kord  in the New 52.  Maybe Ted Kord was never killed in the New 52.  Maybe  right now he is a scientist and maybe he could JUST be starting to  become Blue Beetle in the comics.  Maybe they could do a whole origin  story for him in the modern times with his friend being Blue Beetle and  getting killed leading to Ted becoming the new Blue Beelte... but that  sort of suggests that the current Beetle would have to die right?  Hmm.   Maybe He takes the name of Blue Beetle not realizing its already taken  or something.
I definitely would bring back 
Elongated Man and Sue,  totally undoing the whole Identity Crisis story, undoing her rape and  murder, and him going crazy after and their deaths.  Since  the new 52  seems to have done this with other characters anyway.
I would do a 
Deathstroke: year One  mini series showing how Deathstroke got his powers.  Start it with him  being a soldier who was experimented on, show his family in full.  His  wife 
Adeline, his sons 
Grant and 
Joseph  and his youngest, daughter Rose.  Show him get experimented on and him  becoming a mercenary and all that stuff. Show how his life as a  mercenary changed their family and got them more money, a bigger house,  etc.  Show the family's butler/family friend 
Wintergreen.  
I  would show him become the man he is now and how it effected each member  of his family.  Maybe even show a flash to the future at the end  showing how his choices effected each member of his family, who went mad  and who is dead now and so on.
Almost like a Breaking Bad thing, a  seemingly good family man turn into a monster, and a mirror of Batman's  life at the same time.  Slade could be shown to be the Anti-Batman.
A Fun idea might be to have Earth 2's JSA meet their counterparts on the regular New 52 Earth and maybe thats how the regular Earth gets their versions of the JSA.  Older Heroes who gained powers by meeting their magical counterparts from Earth 2.  Just an idea.
I think I would have had Cyborg, after helping the JLA in the New 52's reboot story where they fought Darksied, after that I would have had him found the Teen Titans.  He, to me, seemed more interesting with the Titans.  But maybe he is always joining the JLA to help them too.