Definitely try to improve your C position. Usually RW's are at a premium and you can ride the hot WW so long as your league permits/number of weekly moves allowed.
In my experience it's been tough to move Kane, I think people are confused on his value. Is he a Datsyuk type or a Derek Roy type..
Either way, I think you'd be well advised to let him play and gain value before you deal him.
Perry will be big bucks since he's currently in the top 10, the buy-low window has long been shut on Iggy and I wouldn't touch Briere with a ten foot pole regardless of how well he's played thus far.
Hope this helps..
MM