In this Health & Safety, Politically Correct world, I don't ever see them going back up above PG. It's only a matter of time before soccer moms and mayors take bigger stances against wrestling, and it becomes like SMS all the time, or dumbed down into bankruptcy.
There's really no financial reason to do it unfortunately. Look WWE first went TV 14 amid the Monday night wars to accommodate D-X and Stone Cold Steve Austin not to mention the most hated man on this forum Vince Russo. There is no reason to go back to edgy television you have to remember this is a business they don't necessarily have us loyal fans interest at heart.
The problem isnt the PG era, its the terrible writing and booking they are doing. The SES was amazing booking and writing and that was PG. The Punk pipe bomb and summer of punk was also great and it was PG.
You dont need to do rated M stuff (mature) to make the WWE better, you just need better booking and better matches.