I'd look at it this way... If you were going to die tomorrow.. (serious -- I'm totally serious here) .. would you feel jipped? What are the very most important things you would feel like you should have done? The greatest achievement in life (imo ofcourse) is to figure out what truly is and is not you. What is the truest, purest reflection of self you can find? Hint: I do not think it will have anything to do with social status, symbols, or any other surface goody.
Like for me, I have all kinds of goals. I want to finish my degree, I wan't to help people, I want to produce more artistic works, I wan't to travel.. on and on. But If I died tomorrow.. I would not be upset about those things.. but I would be upset that I have not had a child yet. I feel that the experience of creating a life, directing and nurturing it, will very well be one of the greatest forms of growth I ever experience. This is my own personal ideal ofcourse. So I would feel extremely jipped if tomorrow I died and did not have the opportunity to do this.
I don't think that you have to have Fi to do some soul searching (obviously) but I do think you have to really self refelct, look inward to understand what is YOU, and not your reaction to the external, or some kind of functioning within the system. What your OP sounds like to me.. is that your not really sure who YOU is... (in no way intended harshly).
Oh ya.. and the reason I steered clear of achievement vs mediocrity is because that is so entirely in the eye of the beholder. You must realize this.