I suggested a heater shield because a tower shield is far too cumbersome for a dungeon environment. A warrior, regardless if they are paladin of an order or not, needs to be able to adapt to their environment. Hence, heater shield.

Mayonite Paladins use water, which is very difficult to suffuse into anything effectively. I would recommend changing it away from water, and to something useful, like lightning.

EDIT: Or, keeping with the water theme, ice. An icy spear works well and possesses the duality of the flaming sword.