That's a lot of questions. I'll answer as time permits in many edits of this post.
Such loaded questions too =P.
Life's purpose/the meaning of life/ my life's goals: I've boiled it down to one thing.
To do my part such that the world is a better place when I leave it, because of my actions.
However such a holistic outlook does little to address the more fine-grained inquires you've put forth. more to come later.