Again, not all uni students are bad!
What about east/south east? There aren't any stations that cover Kensington/Burnside/St Georges/Glen Osmond. The closest would be City, Campbelltown and Mitcham? Maybe Stirling, but I doubt they will be dragged down for an eastern suburbs job.
But yes, more staff are needed, considering both North and South have had coverage issues over the last couple months.