You are doing it wrong. My Knight is a monster. 2 mages and a rogue/ranger, all 3 do amazing damage and crazy crowd control, this and that.
But when the knight is put down or out, they crumble in an instant. His damage is phenomenal, 2h, and the right utility (haste/oath/fort) makes him a 1 man wrecking crew. Currently my knight has 1,314 HP. The next highest is Jahan with 620.
Men at arms skills are perfect for a tank, sadly I went too much hybrid, but I think with pure STR the cooldown would be much quicker.
So yah, 1h and shield is probably much more about being a meatshield, but 2h build is outrageously good. Sorry.