I think if you just want to mash out damage really fast, Kilij is probably your weapon. On your build you probably want it +5 Quality. Get it to +3 normal, then use clearstones to upgrade to quality. Curse Weapon would give it the best DPS and requires minimal investment. But unless you use it in a specific semi-glitchy way, it drains an enormous amount of health from you. To use it without massive health drain you want to get the Talisman of Beasts and have insufficient stats to use it properly, then cast CW with it.
Northern Regalia never stops being good, but it will be out-classed by buffed weapons. So if you don't mind stopping to buff your weapon and carrying around a bunch of spice, it's not great. Also its main strength is lack of scaling, which allows you to just dump massive amounts of points into vitality and just have the minimal stats to wield it.
If you like the moveset, try out the Claymore. You can buy it from the dregling merchant in world 1 for 6,000 souls.