I'd fire Rob Liefield, becaue he's atrocious.
I'd also reorganize the Green Lantern franchise so that each human Lantern fills a different niche, to be most easily marketed. I'm thinking keep Green Lantern the same, with Sinestro and Hal, Blue Lantern starring Kyle Rayner, Red Lantern starring Guy Gardener and Green Lantern Corps starring John Stewart in a federal role, working across GL sectors.
Detective Comics would become a sort of Batman Presents book, reintroducing Spoiler as the daughter of the Riddler, combining his character with Cluemaster's. I see that as a bonus for both characters. This would be followed by an Alfred arc, in which we learn that he's gay, because it makes sense, is a positive statement about the raising of children by gay people and would piss off all the right people to ensure enormous sales.
Amanda Waller would get fat, slowly.
After a while, an Earth 2 Presents book would be launched. Also, the Freedom Fighter characters already introduced would be revealed to be the government-sponsored team on Earth 2. James Robinson would act as "showrunner" on these books, and be basically allowed to do as he pleases, because that's the best way to coax greatness from him. If fan interest is maintained, I'd try to get an Earth 2 anime in the works, as it seems like it would hit a lot of the right notes for one of those and would help expand the market.
Supergirl would join the Teen Titans, led by Redbird/Tim Drake. Superboy's powers would actually be tactile, and just using generic telekinesis would be forbidden.
The next artist on Justice League would be stuart Immonen, whose lead time combined with his generally high output would result in each issue being 30 pages of story, at no extra cost to the reader. I'd generally encourage shorter, faster stories tying into a larger narrative, like in The Flash, where that's working exceptionally well. The Justice League needs to be punchy.
Ben Caldwell would be given the chance to do his Wonder Woman manga, but I'd bring in Amy Reeder to do whichever character she wants, as well as others. Marcio Takara, maybe? Make a thing of it. Absolute creative freedom given, too. It's an alternate world, so why interfere with the creators? I suppose this would have to fall under the ELSEWORLDS umbrella.
No event books, but some interrelation between the books. Also keep the line at 52, minus minis and one-shots, as that's proven to be a nice number.
I'm going to stop now, because this topic is clearly prone to rambling.