This is subjective though. My wrist is 17cm/6,7" and I think my 44mm pilots look fine. I even wear 47mm and 50mm watches and still don't feel like I'm wearing clown shoes. ;) Actually, I always prefer watches larger than 42mm for myself. It really depends on the case design though. As long as the lugs curve with your wrist it'll look good.
I have a 6.75" wrist, and the CW C10 at 42mm fits well. Don't think I'd go higher than that, but yeah it does depend on design, the Stowa Antea being a prime example where I have the 365 instead of the 390.
Btw did see your post asking for C10 pics, but I absolutely suck at watch photography. I tried :(