We are in the same boat (deferred from EA to RD), and while I certainly hope that my son gets an appointment, I would never recommend to him (and he's not considering as an option for himself) doing a year of college somewhere else and applying again. The SAs are a great option, but they are by no means the only great option. Indeed, my own father, a WP grad, consistently told me as I was preparing for and in college that he thought ROTC scholarships were "a better deal," as just one alternative, and I took that advice.
I was commissioned with a guy who spent our freshman year somewhat bemoaning that he hadn't gotten in to WP and considering reapplying. Well, he ultimately opted against it (this was the early '80s) and retired a few years ago as a Special Forces O-6. I'm quite sure in the fullness of time he didn't regret his choice. And I was commissioned with another guy who turned down WP, and I know he didn't regret his choice.
I would tell my own child if he asked to get on with life.
Just my $.02.