I'm not so sure the PGA Championship needs a helping hand, but I'll play along.
I like the PGA Championship, because it's one of the four majors, and every professional golfer treats it as such. That's why, in my opinion, its place in the world of golf is secure, and its status won't ever be diminished. I like that it usually doesn't care if double digits under par is the winning score. I also like the fact that it goes to some golf courses that are not looked at by the USGA. Some of them, like Kemper Lakes, end up being a poor selection. But that does not mean that Payne Stewart did not win a major there.
I like the mix of some classic, old courses with some new tracks. My 8-course rota would include Baltusrol, Whistling Straits, Atlanta Athletic Club, Riviera, Inverness, Valhalla, Southern Hills, and something in the Pacific Northwest. In my opinion, those are eight (seven specific) worthy golf courses that have proven they can stage a major. They are scattered throughout the country, which I think is important.
Let's face it...the PGA Championship is never going back to match play. Television simply won't allow it, as ratings would plummet unless the final has two elite players in it (which almost never happens). Also, why would the PGA of America choose to take their championship to another country? Television won't pay them any more money, and it would cost more to have everyone associated with the event travel there multiple times. Like Deepthroat said, "follow the money." I doubt the PGA of America has enough in their coffers to take a hit like the USGA did this year at Merion.
As much as some people don't like to admit it, the PGA Championship is a major, one of four each year. It's a major because the players deem it to be. There's a reason The Players Championship never became "the 5th major," despite the PGA Tour's deep desire for it to be. The players have never decided it is a major. I like the PGA Championship. I've said it here before, but it's like what coach Norman Dale said in one of my favorite movies, Hoosiers: "I would hope you would support who we are, not who we are not."