I've got serious issues with Worf.

While I admit he does have the Klingon warrior spirit. I have always found him to be a bit of a tool. As well as having the tendency towards cowardliness when too much responsibility is placed upon his shoulders. Look how many times in TNG, Deep Space 9, and even some of the movies. Where he had the opportunity to be in charge as a leader and either denied the responsibility, or fucked it up.