In my opinion your best weapon for Navrey should be with the highest fire damage you can get. Enhancing an iron wepon with Bronze gets you 40% fire damage. As for mods, I would typically go SSI, HML, HSL, DI, and Spider or Arachnid Slayer. For Navrey, with 100 DI, Chivalry's Enemy of One (EOO) and Arachnid Slayer and you are at max damage. Or 100 DI plus Spider Slayer gets you there too.
As for weapon types, choose the hardest hitting Armor Ignore (AI) weapon for your weapon skill that you can swing at max speed of 1.25s per swing. This is base weapon speed, SSI and Stamina dependent. I like the following with 35 SSI and 180 Stamina:
Mace Fighting: War Axe
Fencing: Leafblade
Swords: Longsword (Broadsword or Bladed Staff with 35 SSI and 150 Stamina or 20 SSI and 180 Stamina)