I would tell you that the most important concerns Jonathan Drouin. Drouin was not on the ice, but despite everything, he remained on the side, as a spectator. We never see that normally, but obviously, the Habs forward was eager to listen and see his new coach at work.
It was a remarkable gesture, especially since Drouin had several good discussions with St-Louis. We clearly see a change of attitude in the locker room, and with Jonathan Drouin.
Take a look at the interactions:
St-Louis and Drouin at Practice