Hee, I started this thread, and it's come alive!
I think that Cedric is pressured by his father a
bit, but the choices are still mostly his. I think the most important point is that Cedric is very modest, and dosen't like being in the spotlight
all the time. When his father mentions on the way to the QWC (in GoF) how Cedric beat Harry in PoA in Qudditch, he shows how humble he his, wanting his father to understand what really happened that day.
He might come accross as meek and loyal to his father, but I think it's more modesty that is his shining trait.