I'm looking at new packs at the moment any suggestions?


Just one quick suggestion, hold off on buying a pack until you have a very clear idea of how much space you'll need in it to carry the maximum load you'll need it to handle.

Another quick thought: public transportation to towns near the PCT is very limited. Intercity bus service, such as the Greyhound or Trailways bus services, that once flourished as a means of getting from one small town to another, are a mere scrap of what they once were. Trailways vanished and Greyhound almost has.

There is public transport from San Francisco to Yosemite, so that's covered, but you'll almost certainly need to hitchhike from your final trailhead to a town of some size before you can connect to public transport again. Getting around in the US western states is quite difficult without an automobile, but especially to the remoter, wilder areas you are aiming at seeing.