All the stories that keep coming out, about him being a secret alcoholic and feeling like he's in over his head, make him seem more interesting and relatable, really.
He discussed that on Howard Stern (the alcoholic part), and in short, that's not the case at all.
I actually like Fallon. I couldn't stand him on SNL but a few years ago start watching Late Night and was into it. I do completely agree he laughs way too much but I've heard stories from celebrities (again, on Stern) and they mention they love going on his show because he's "great at laughing" and makes everyone feel comfortable and he may lean into that a bit too much.
Anyway... that's my take on the host of the Tonight Show in this thread about Cory Kennedy