I found a Claire/Peter comm. So far, I have not found good fic yet, though. Life so sad.

I could give you fanfic recs, but no Claire/Peter ones. So not my pairing. (Not because of the uncle/niece factor, because of the 15 years old/26 years old factor and the imo lack of any romantic interest on his side at the very least. I did write a gen story with Claire and Peter as the leads, but it's set post finale, and you haven't reached that yet, have you?)

Meanwhile, here's a Heroes stories rec page:

http://mimesh.livejournal.com/46444.html