I shudder to consider what your favorite is. "Shades of Grey"?
Jammer gave "Barge of the Dead" a full 4 stars out of 4, I'm pretty confident I have good taste
And you don't need to shudder, you can check out my top 30 favorite trek episodes video in my signature.
Also, I don't think "Second Skin" is derivative of "Face of the Enemy" at all. I was on tenterhooks for most of "Second Skin" wondering whether Kira really was a Cardassian end enjoying Kira's mental acrobatics trying to get her head around it all......nothing like that was on display in "Face of the Enemy".