Even though statistically Korver is the better player right now, I would keep Parsons. I just feel like he has more of an opportunity to maintain his value 2nd half of season. You have to remember that Korver is a very injury prone player. Harris could also effect his value, and ATL is constantly involved in trade rumors, so his status going forward is more up in the air than Parsons.
I don't think it would be the worst move ever, and there's a chance it could work out in your favor, I just personally wouldn't do it.
Is Parsons really the most droppable player you have? I think Parsons/Korver would be a good fantasy duo to have.