IMO the locations are very different: the old CBD versus the Rocks. I basically agree with you that the PH building isn't so impressive, just it's location and views, if you have the good rooms with views. IIRC you can't use TSUs either to get an upgrade.

Personally, in Sydney I've enjoyed the Observatory hotel on the other side of the Rocks, with views of the container ship and cargo facilities, but still an easy walk to restaurants, the modern art museum, and ferries.It used to be an Orient Express Hotel and I was treated well with FHR bookings.