New banner and orbs

Well, we haven’t seen his stats yet. But judging by his stats in the story mode, he probably is going to be tanky, I think it is a good idea. He is pretty scary with that Steady Stance 4, with guard, and VF. That’s basically a discount Special Fighter, but with a follow-up attack.

I Guess units units with a DC weapon would do better with SS4, that could be potential fodder. I think M!Grima could use Steady Stance 4 better than Surtr. So you can fodder him for that as well. Imo, I’d keep Grima.

No, not unless you need SS4 as fodder for something else or like Surtr as a character. M!Grima is still better with his native adaptive damage, DC and VF imo. All that flat damage sounds great, but keeping out of Surtr's range especially if you have a dancer is easy.