I have only seen Trinity and St Aloysius.
From St Aloysius, Harrison Williams is a good candidate. He's very good in the air (lineouts and restarts) and gets around the park well.
From Trinity, Clunies-Ross, if fit, must be in the mix at wing or full back. Morsello, if fit, is worth a run at hooker. Satiu has been spectacular this year and needs to be there. Then you get a problem. Orr and McLean are very good ball-running front rowers but Trinity's abundance of riches in this department has pushed McLean into the second row. You wouldn't pick him in the second row in a representative team, I suspect. So the selectors have a tough choice. I guess they pick Orr in the position he plays for his school, but it's not an easy call. Neither Malaki nor Ola would be out of place at the next level. Clark should be the fly half. Trinity has won something like its last thirteen Associated Schools competition games so if they get seven or so players in the CAS 1sts, no-one could complain too much.
From Waverley, Whitaker and Paterson must be in with a good chance.
Cranbrook and Barker will have good candidates I haven't yet seen this year. Barker's winger, Haltmeier, impressed me last year, though no-one else ever says anything about him.