Highlander, on top of getting passive Crit Attack to 2H Swords, gets skills like Crown (Zornhau + Crown combo, constant Shock on magic enemies), Skull Swing, which reduces enemy’s defence to ZERO and Skylinet + Crosscut combo, which rips enemies to shreds, even after nerf.
Cartar level 3 on top of getting Knockback, also get Collision damage, great skill for CC.
Barbarian can offer to Doppel Frenzy (but on high levels +400 damage don’t mean that much) and Seism. However, it’s skills fall off later game, while Highlander can still maintain itsels thanks to utility it’s skills provide.
Stun doesn’t last that much.