I am of mixed Sephardic and Ashkenazic parentage. I view this as allowing me to behave Sephardically when it suits me (for instance, eating kitniyot for Pessach) or Ashkenacikally when it suits me (for instance, not wearing a Talit until my wedding). Another example is that my tefillin is Sephardic, but I tie it Ashkenazically (though the ש comes out backwards).
Someone once told me that this is wrong, and that I should follow the customs of my father. My father, however, grew up completely secular and only started observing when he had a family of his own. In this case, the customs of my father don't follow the customs of his father and the ancestors before that.
In a case such as this, whose customs should I follow. Is it correct to pick my own customs when I don't have the customs of my forefathers to fall back on?