Penny doesn't K enough for you, but you like Fausto? He's got the worst K-rate of the bunch. I know Penny's K-Rate is down, but when he's on, it's a solid ratio.
If you look, he's been up over 6 per 9 lately, and for most of last season, he was in the 7 per 9 range.While not jaw-dropping, that's certainly solid.
Carmona certainly can do better than he's done lately. His GB%, which is his bread and butter, is just as good as last year. However, last year he had an absurdly high strand rate. Even with the higher probability of DPs from his GB ratio, you can't expect him to maintain an 80% strand rate. I don't see him ever producing like he did last year again, unless he gets just as lucky again. Actually, luck is probably a poor way to put it. If they ever put a gold glove infield behind him, I could see him having a shot at 80% again.
I keep thinking that Sanchez is actually going to fall apart one day. His K/BB is very weak, and his strand rate is very high (and constantly has been, for some reason). Even with 150 IP under his belt, he's still young. I consider him an unknown and, as such, high risk.
Assuming you're playing traditional categorical, Penny has the best shot of helping you out, imo. He's got Manny in his offense now, and he's playing for a "contender."