What are good things to have for a memorial event for a soldier who took his life?

Tough question. When my cousin killed his self his sister displayed pictures of him when he was enjoying life.

MSgt David Hoffman CH (CPT) (Join to see) Maj Rev. Fr. Samuel WATERS - Traditional RC Priest CH (CPT) (Join to see)
Any suggestions?

You will be celebrating his life, his accomplishments and your positive experiences with him. Everyone there will know the circumstances of his death, but that's not what you want to memorialize, just as you don't memorialize memorialize other tragic death circumstances, i.e. he burnt to death as he plummeted to the ground in his burning aircraft would be handled by he was a good pilot who could always be relied upon to pull his load.