Most of my beliefs around suicide are actually reflected in this great article: The Spiritual Consequences of Suicide
The main problem for me is that I think about who chooses suicide, and why. A healthy, wise person who is living their desires and dreams certainly wouldn't want to cut their experience short. So if someone does want to, then they either aren't healthy, aren't wise or aren't living the life they want to live. Now, most of the time, health, wisdom and quality of life can be improved. If it can't though, then that's another matter.
It all comes down to accepting the consequences of actions. That person's unique presence in the world will be lost, thei path will never be travelled and their expression to the world will never be experienced. There will be a gap. Not sure if that's a good thing or a bad thing, but it's something that will happen.