I think Nietzsche was ILI E5. Definitely E5. Te >> Fe. Logics > Ethics. http://www.brainyquote.com/quotes/au...nietzsche.html
E5s are relying on rationality and are grounded in the head quadra. It seems almost impossible that an ethical type would fall into a fixation that is so rational (head-head), since their conscious focus lies in the realm of people handling. True that the enneagram fixations are largely unconscious, but the pattern seems to hold water when typing people I meet. E5s I know are ILEs (Einstein), LIIs, ILIs and SLIs, and probably no other types.
Same thing for the other "pure" fixations - E8 and E2:
E8s rely on instincts and are gut triad - I don't think an introverted intuitor could ever be E8 (gut-gut). (instinctual/reactive of the gut triad). How can you have a fixation that gives perfectionism in external execution when that lies in the parts the are the furthest away from your conscious processing? I laugh at the thought of an IEI E8... I have never seen alpha E8s either. EIEs (Steve Jobs), SLEs, LIEs, SEEs, LSEs and SLIs can be E8s
E2 rely on feelings in the image triad (heart-heart) - I think only types with strong Fe and possibly strong Se in addition, like ESEs and SEEs, can be E2s. Theoretically I would like to believe ENFxs could also be E2s, but I have never seen one.
As for the other E-types, there are similar patterns, when you go deeper into the enneagram, but these patterns are a bit less obvious, so I won't go into details. Surprising type combos I have seen are LSI (Katy Perry) and SLI E7s, and I'll leave your theory the benefit of doubt for that reason.