It honestly depends on what you mean by "overpowered". Also, since the only competitive game I've been playing lately is Urban Rivals (a rather unconventional F2P CCG that I highly recommend) I'll be using examples from that.
Sometimes something is incredibly solid and has no weaknesses, but this doesn't make it overpowered. For example, in Standard the Sakrohm clan are what I've started calling a "Swiss Army Clan/Deck", meaning they have most every trick at their disposal while still being solid. They aren't OP though, as I generally get 50/50 results against them when I use my hyper-specialized Ulu Watu deck which has tons of weaknesses. Compare this to the La Junta clan, with whom you'll usually draw a hand that can kill your opponent in two (out of four) turns while also having a good mix of utility abilities and solid enough stats to deliver the nukes when you need to. I usually get stomped by these guys in Standard, but even then I wouldn't call them OP because they lose either their edge or their utility against the various Stop decks, which I don't happen to collect much.
Lastly, something overpowered can actually make other things balanced. My Urban Rivals example for this is Kalindra Cr of the Frozn clan. For the 98% of you that don't play Urban Rivals, Kalindra Cr is that card that you get very wary of when you see your opponent using it. She's strong enough to secure victory single-handedly when played right, having really good synergy between her ability and bonus as well as with the rest of her clan. She's not broken, as stopping her ability or bonus takes the edge off and damage reduction defangs her entirely, but she's certainly overpowered. However, when she was banned from the Elo format (UR's "super legit" game mode) the Frozn pretty much disappeared entirely because she was the tentpole card holding up a bunch of alright/sub-par cards.
The Huracan and the Uppers, though? Fuck that noise with the nerf stick until it stops moving.*
To answer the question, though: No, but this is rarely intentional. I typically gravitate to rather specialized playstyles in which winning is both fun and plausable, but I don't intentionally seek out things that need the nerf bat.
*-EDIT: Ironcially enough, I just kicked the ass of some chump using a split Huracan/Uppers deck containing some of the more irritating cards those clans have to offer (Noctezuma, El Divino, Kayazan, and Lady if anyone's interested).