Worf really grew up when he moved over to DS9 after TNG had used him as comic relief and the bringer of the "let's kill everything" plan. His commands in DS9 did show the "let's fight" mentality but tempered.
In DS9 and Defiant operations, Kira seemed outmatched, but give her ground operations and she's set.
Jadzia was always a better second banana than a leader.
Worf got my vote.
I don't think Worf grew up so much in DS9 so much as he was put in more situations where his attitude would cause problems, like in Rules of Engagement. He was still very emotional and easily thrown into rage, his behavior in Sword of Kahless was absurd. If anything he became less Federation-like in his values. He refused to kill Toral because "It is the Klingon way but it is not my way". Then in DS9 he was like "Crap, I should have killed Toral!"