The idea itself remains to exploit the assets of the Brigantine: not only its flood preference but also its great mobility and speed. Also, the piercing status offers great synergy with many other DPS types thanks to both its armor reduction effect and some furniture combining flood and pierce effects. That being said, alternative solution such as torn sailed work well too, therefore the whole loadout is subject to variation:

• Main, broadside, weapons: Rahma vs Dahaaka:
  Rahma's torpedoes are the "high skill high reward" solution, especially against bosses due to their insane DPS if used well As they have no piercing dammage, you can also consider replacing piercing perks with torps oriented furnitures to focus more on the flooding dammages.
  Dahaakas seem a bit more comfortable with their higher speed, and versatile with their status. Moreover, they also benefit from the pierce/flood furniture. They also work better against group of ennemies rather than single targets.

• Bow weapon: 10 Suns
  Arguably viable alternative would be Great Springald or any sail tearing weapon for the immobilizing ability, or twin winch for raw dammages. 10 Suns remains the best solution as long as you combine piercing with flooding.

• Main furniture: multiple solutions are viable, as long as you adapt some of the minor furniture accordingly:
  *Rope locker helps to maximize mobility, especially after a ram -to combine with the secret cache and various mobility oriented furnitures.
  *Munition mixer to expand ramming opportunity -great with mobility furniture to rapidly turn back and ram again.
  *Megaphone if you want to focus more on the torps than ramming -consider replacing iron cladding then.
  *War drums for more defense and durable mobility.