Which BHector IV?

Either pure physical tank, with -res,
Or average tank, but still good vs mages with -hp. I would keep both and summon more to get better IV. The banner is far from clise to its end. Tbh, they are harsh. Brave Hector shines with tanking everything. Even if you do not aim for ideal IV (-spd +att/def/res), you could still get a neutral or a -spd +hp.
If not...well..+att/-res. And consider him a physical specialist. He will do a very good job. But vs dragons and mages ? Not so much, like other hector.

Hector is someone who probably wants to preserve his Defense and Resistance. With that being said, there's really no choice but to go with +Atk/-Res. He is going to take significantly more damage from mages and dragons, and might be worse for Arena with that superbane. Although, never underestimate Armor buffs. With Fortify Armor, he is still going to reach 30 Resistance which isn't bad at all; with Distant Defense seal, he gets up to 36. Also, he is going to have much higher Attack (56 and up to 66 with Hone Armor and Ostian Counter).

If the only option is to choose between the 2 then +atk-res. While both banes suck for him, at least one has a good boon,