On Self-transformation
"Askesis" is a Greek term that I am quite fond of. Perhaps the most literal translation of the word is "shaping of the self," although that does not quite capture its essence. Indeed, a definition of the word must necessarily allude to the introverted and contemplative process that a person must go through to experience "askesis." Thus, Askesis is a sort of spiritual exercise. Personally, I believe the word is also closely tied to the term "periagoge," or the turning around of the soul. The latter comes from the allegory of the cave in Plato's Republic. It is this "turning around" that allows a person to have the necessary perspective to experience that process of self-transformation or "askesis". I'm here reminded of Pico Della Mirandola as well, the fifteenth century humanist philosopher who said man has the capacity to rise to the status of the angels. And then there's Nietzsche's concept of the "Ubermensch" or overman. It seems the Western tradition has always been fascinated with the idea of re-inventing man and re-shaping him, sometimes even literally.
What I ask myself is, where do I go from here? What chameleon-like feature will I adopt now? And, can I really choose?
What I ask myself is, where do I go from here? What chameleon-like feature will I adopt now? And, can I really choose?

Character reinvention is an interesting concept. To a certain degree, it is possible to change, but the essential character, I think, is established long before adulthood. Part is innate and part is moulded in early childhood through environment, influences and experiences.
Crisis or a major shift can also create change as can the power of the mind, but only in some instances.
These are perhaps what you essentially are refering to?
It would be nice to have a reference, but I guess, if other relative traits are already in existence, then a person could by thougt and action become more bold, more honest, more outgoing, more confident, etc.
If one went to a place one wasn't known, and attempted to live life and introduce oneself as someone other, in the end one wouldn't be able to keep up the facade and ones true character would emerge. In other words, no, I do not think it possible to simply adopt opposing features contradictory to one's essential character, but with time, one can learn them to an extent.
...the whole Nietzsche thing is infinitely scary with ties to ethnic cleansing and genetic modification and cloning, and not least Darwin. One can almost see the future full of strong, intelligent, beautiful people, and the mind boggles.