Honestly most times I see the farmboy thing get brought up it's treated like a handicap and how another character might have a chance at taking out Supes. The farmboy thing has no relevance to Superman and doesn't translate back into his life as Superman effectively. It's as far as I can tell there to enhance the "regular guy" angle they've been playing up since crisis other than that it seems irrelevant.
Clark back in the day would have given Kara and Bruce the business, the fact that he's at best struggling with them but often depicted getting his clock cleaned by either in a variety of mediums shows the guy has fallen quite a bit from his prime. That's not just a power differential thing either but the shift in his whole attitude about being a superhero in general, I was reading The Earth stealer a few weekends back and when Supes is called into action he's so dejected and half hearted about it all you get the feeling he's not the type of guy who probably enjoys the struggle of the Superman life. The farm boy thing is at the heart of that because it's taken the characters focus away from being a hero and reigned him in to "relateable". But Supes is a character imo that needs to be allowed to spread his wings and fly.