Mind you, the best rookies go straight to the NHL. Looking at the list of the best rookie seasons in the AHL since '85, I see a couple of current Sens (Ennis, Brown) and a former one (Connacher).
Not exactly murderers' row.
https://www.eliteprospects.com/awards/ahl?name=AHL+Most+Points+by+Rookie
Not exactly murderers' row.
https://www.eliteprospects.com/awards/ahl?name=AHL+Most+Points+by+Rookie