It has been said that the law school application is the candidate's first case and I would agree with that. The big advantage here is that it can be done solely on the applicant's term. One of the names of this game is to separate yourself from the pack. A note of caution. Be careful in how this is done.
Confidence is a fine quality for a future law student and lawyer.
From an admissions point of view however, arrogance is something else. The line between the two is fine, but it is crucial that the applicant understand the difference. As for the weaknesses part of the formula, I am well aware that there are some people who would say that you should not discuss your weaknesses in a personal statement. They argue that to deal with your weaknesses only draws attention to them. There is merit in that, of course.