I would ride you out of town on a rail.
Winning teams don't trade Kimbrel, That would be like getting back (in terms of value) Wood, Gilmartin, and Sims. Not a bad return, bu not a trade you make as a winning team. We don't need prospects, hell we don't even need a 3B for next year. We need a closer who can lock down games for as long as we can hold onto him (which shouldn't be an issue until it's FA time for Jason and Justin. Even then, it may not happen if we don't keep Mac, I'd gladly ship off Medlen to keep Kimbrel)
Smart organizations make trades like this. Sure, we don't need prospects now but we will once all of our money is locked up into 4-5 players. If you keep producing cheap talent then you can ensure that Freeman/Heyward/Simmons/Minor/Teheran are Braves for a LONG LONG time.