Taken from FoxSports:

"The NFC was 3-1 vs. the AFC Week 16 and has a 32-30 lead in this season's interconference series with four games remaining Week 17: New England at New York Giants; San Francisco at Cleveland; Buffalo at Philadelphia; Minnesota at Denver. The NFC last won the interconference series in 1995 (33-37). The AFC leads 409-331 since."

So as of right now, the NFC is the "better" conference.
As I've said, I think the AFC is more top heavy and bottom heavy, and the NFC is more spread out.