I do not think of our Amarrian (or the Caldari) culture as restricting the sense of self - rather, I would say that it is experienced differently.
To my feeling, the Gallente en Minmatar put a large emphasis on personal independence and the development as an individual. While of course they identify also with their culture or tribe, still I would say the emphasis lies on the self, rather than the group (please forgive my broad generalization here).
I think that we, and also our friends from the State, have a much more interdependent view of the self. The self is defined by your share and role in the common. Rather than your very own accomplishments, what matters are the interpersonal relations and in particular the relation and harmony with the group. To me, that is the deeper meaning of the code of Demeanor, as you mention, in particular the verse “Be Respectful. Uniform Thought is the Way of Life.”
For our valued friends from the State, the corporation is this group. As for us, our common faith defines it. I would claim that cultures that have the “interdependent” view of the self rather than the “individualist” view of the self are better able to give a person the sense that their existence is meaningful. Provided, of course, that these persons fit in the group and are flexible enough to evolve with it - hence the stern warnings of the Code of Demeanor.