Style is a huge issue. See my essays on this.
Poker Playing Style Part 1
Poker Playing Style Part 2
I believe you must develop a style unique to your temperament, risk tolerance and personality. This conserves energy and creates opportunities to play in "the zone".
Especially in tournaments.
Basically I think you play a base style that works and then you vary from there with intentional adjustments based on the situations.
You must develop your own style. This is impossible without intentionally introspecting about yourself and your relationship with your game.
Be careful, or you'll expand your consciousness.
See also:
Poker and Introspection