Re: Measuring if/how martial arts helps one become a better person
I can not answer for all Martial Arts, although I do believe that seeing what you may be able to do to an attacker should help make you less afraid and thus better.
As for Aikido . . . It is my understanding and experience that if you take the time to truly understand and accept it's teachings you learn not to fight, but to flow like water, in all aspects of your life. In my Humble opinion . . . better. :-)