I've been following you and @paulg as well as many other YC members for a long period and I'm quiet confident that you'll adhere to the vision/idea behind a pro

I've been following you and @paulg as well as many other YC members for a long period and I'm quiet confident that you'll adhere to the vision/idea behind a project that I'm about to start this year. Do you recommend that I apply for YC really early, like now, just to present the idea ? Or should I develop it and apply with a prototype ? Or should I launch it and then apply ? In which case can YC help the idea to have bigger chances to succeed ? And in which case you do you most likely accept the application or at least give it a better chance ?