Being honest about your opinions with yourself is the only filter for noise in this World.
Being opinionated doesn’t need to be vocal, it just requires that one stays loyal to his ideals, and not carelessly abandon them in a contrived effort for social harmony. Not controlling your neuroticism and need to negate conflict is what is truly selfish.
Also, discipline and the willingness to sacrifice comforts seem related. One’s commitment to an objective can be measured in how much one is willing to suffer in order to achieve it.
Finally, what’s with all this strictness and morbidity? I feel that it appears as pessimism, cynicism, depression or Puritanism to others. Quite the opposite – life is beautiful, I just try to be realistic about it’s cost of admission. After a sober assessment of our limitations, I dwell on what could be and book titles like “The Further Reaches of Human Nature” appeal most.