Is there more risk than reward in writing to a prison pen pal (no romance, just to show kindness)?

There is a risk but I believe there is more of a reward than a risk . And the risk is up to you. Remember you are in control not the person inside prison. And do not let them have control. You say you just want to show kindness and I think that's a good idea. I would get a PO box if you dont have one . But people in prison love getting letters and I think you will find it rewarding