We should take the Detroit approach with almost all prospects, except the supremely talented ones (Rielly for example).
Stick to that patient approach (which Burke/Nonis have largely done, unlike Fletcher and JFJ), and it ends up so you don't really have to wait, because you'll have a constant influx of young talent anyways.
Over the next 1-2 years, we should see Holland, Granberg, Ryan, Percy, Ashton, and D'Amigo taking spots on the Leafs roster.
2-3 years from now Leivo, Finn, Brown, Biggs, etc can start taking on roles. And then 3-4 years from now Gauthier, Verhaeghe, etc.
Obviously not everyone will make the NHL. But if we slowly develop everyone, get them several years of AHL experience, and then bring them in when they're ~21-23 instead of 18-20, we should start getting more our of our farm system.