I think a lot of it can be chalked up to people's individual interpretations / biases more than the toughness system, which is admittedly underutilized. And even when the script did lean on it more, it was usually minute tonal changes to the dialogue.
Well, and the decisions you make are remembered and inform later segments, but that's separate from toughness.
It means you'll have a bigger influence over him, which besides the buddy buddy stuff with Edwin, could also play a role in the club politics side of the plot.
Oh, and also it'll give access to some scenes involving him.