The hospital next to Williamstown Beach station is a small hospital, and most people would either arrive by Car or Ambulance. Perhaps when Ambulances start running on rails, this station can recieve an upgrade.
Disregarding the occasional school students, East Camberwell is possibly one of the quietest on the network, there is no way in hell this station will ever need to become premium.
Hawksburn is quiet, and there is nothing of intrest around it. Trust me, I live there.
Heyington is the same deal as East Camberwell. Only gets used by students in a couple of trains before and after school. Outside those times it's dead quiet. Heyington needs to become wheelchair accessable before it gets premium status!
Primary school students don't travel to school by train... well, most don't. This is definately not a reason to give a station premium status.
Many High School students travel by train, but the times when stations are busy are usually restricted to around 7.30-8.30am and 3-4pm, before and after school respectively. This does not justify around the clock staffing. Stations that are busy just because of students (like Heyington, Kooyonh, East Camberwell, Strathmore... etc...) do not need premium status, they need part time station hosts at the most.
And then of course, there are Universities, where classes ran at various different times, and students are no longer living at home, and must rely on public transport. It is the universities that generate public transport demand, not the High or Primary schools.
You seem to be missing the point. Premium Stations are selected because they are busy around the clock, not just when the school bell rings. Premium Stations are not selected by community places such as schools and hospitals, or anything else, and are not selected because they are junction stations or at the end of the line, like some people think they should be. Take Surrey Hills for instance, a very busy station, recently upgraded to premium status, yet the only "attraction" it has is a small suburban shopping strip, which many stations have near them. But... Surrey Hills is genuinely busy, so this is just one example of a station with no "attractions" yet it is premium.