Notes from author
My idea of what a BK might be built as.
The BKGA is the heaviest Black Knight Weapon, if you don't plan on using it: reduce Endurance until barely a mid-roll - then heighten Strength and/or Dexterity accordingly. Never go below 40 Endurance, however.
The Wolf Ring raises the poise past the in-game Black Knights' 80, so you can swap it for whatever you like that works i.e: Chloranthy Ring, or Hornet Ring. Do remember that removing Wolf Ring isn't quite as true to in-game Black Knights' poise values, but again, anything that works is fine.
Do suggest anything you think of. Have a good time with this - I did.