I think it depends on how one defines "Aikido." Most people seem to use the word to describe a certain way of doing martial techniques. If that is your definition, then I definitely think that it is highly unlikely to improve your life.
In reading the Founder`s words or listening to his lectures, I think it is clear that he meant for the art to help people better themselves. I also think that it can be logically argued that if one does not become a better person, that person is not doing Aikido.
All of the "do" arts have at their core the intention to develop better people. Terry Dobson, a live in student at the Aikikai Honbu Dojo while the Founder was alive, wrote that Aikido saved his life, meaning that he definitely became a better person through Aikido. His book "It`s a lot like dancing.." has been very inspiring to me.