Bokken & Jo
I have always had difficulty with identifying Aikiken and Aikijo training as "weapons" training. I, like most others still call it such, but I am uncomfortable with it.
For my own personal perspective, the bokken and jo allow me to focus my ki beyond my body.
The bokken is used to "cut through" my illusions of myself. After 1,000 cuts, many illusions fall, the primary one is that I am getting younger.
The jo gives me the ability to "reach out" to others.
Forms are interesting and give me something to do while I am learning about the bokken and jo, ultimately the form is not what is important. "Piercing the center" and "reaching aiki" are the only things which count.