Well, I have a theory that sort of combines the two concepts:
Out of the three main story elements, everyone has one area of super strength that they are a natural at.
About about your current work in progress, think back to the very, very beginnings of it when that first spark of an idea came to you. That thing you built the entire story around. Was it a character that inspired the story? A place where the story would happen? An idea for a general concept or a fabulous conflict? When you get a new story idea, that initial spark-- character, setting, or plot-- generally comes in the form of the thing out of those three you are best at.
So... if I'm a natural at writing characters that feel real, does that mean my plot and setting are going to stink?
No. It just means that you are going to have to try harder on your plot and setting than you had to do on characters. That those things probably aren't going to be strong enough in the first draft, and it will take a few rounds of revisions to get them up to the same level as the thing you've got super powers at.
Okay, so a few examples. I would dare say that Stephenie Meyer's and J.K. Rowling's strengths are in characters. Stephenie said that her characters came to her fully-formed (a huge hint that characters are her strength). And in both of those series, wasn't it amazing how real the characters-- even the minor ones-- felt? And I think than Dan Brown's, John Grisham's, and James Patterson's strengths lie in plot. And that pretty much every high fantasy book's strengths are in setting.
So what do you think? Do you have one area of super strength and other areas that you have to work really hard at to get to the same level?