As for the "Global Peace Agency" -- honestly, I have NO idea. I like the idea of having another intelligence agency out there to go with Checkmate and the DEO (assuming both got through Final Crisis, and I'm not sure they did), since that opens up more options for plots involving subterfuge and intrigue.
However, I'm not at all confident that most of DC's writers can write a really GOOD intrigue/subterfuge plot. Maybe Greg Rucka will use them in his Detective run? Gail Simone, Marc Andreyko (guy who wrote Manhunter) and Paul Dini would also be competent to do it, but I can't think of too many more who would.