Black Zenith [Adventure RPG / Chapter Four: Fires of Heaven]

I don't think you guys have noticed it yet but I built Watson as if he had to last on his own because I thought he was going to fight his way through like Takumi and Jane Doe.

So how long do you guys think your characters would last alone, against, say, a boss? And who would you think would win if it was against each other?

Also, I'd like an opinion on Watson's overall build. What would be his weakness? (these questions are all for before this level up)

E: Also take away equips because Thunderpaw is OP at the moment.