Ladies and gentlemen, not all ninjas are equal. They will never be all equal. The game is designed to spend hundreds of dollars to get the stronger ninjas, this won't change.
As for Toby, he isn't broken at all, you just don't know how to play against him. Mabui and Kakashi beheading blade both have mystery skills that will stop him reviving if killed. Use any ape mystery first to proc his dodge then hit him with your strong single target combo.
He would always be my second target usually in any pvp fight.