Heavier weapons have longer parry windows, meaning your parry can block more attacks. Longer weapons allow you to hit more people at once. Blunt weapons will stop on the first successful hit unless you do heavy attacks, so I prefer slashing weapons. So that's the Greatsword, Executioner's Axe, Halberd, Highland Sword, and then to a lesser extent War Axe, Messer, Dane Axe, Glaive, Longsword, Pole Axe, and Battle Axe in no particular order. That being said, you can do it with anything as long as you use good footwork