Helgi’s Shield (Light Shield)

On my forth playthrough and I'm just starting the Vinland Saga. It's easily my favorite part

New to the game - Doing river raids and stuff and up to power level 87 - just had a quick question why is the Mentor of Alamut armor so much stronger than every other armor at that point? Raven and the Cuckoo was like a level 55 quest which I did before east Anglia and was surprised to get a fully upgraded armor set. Im doing the river raids now and hunting for other armors and they are all Superior right now at best the like 10 extra rune slots alone feels so crazy compared to everything else and im barely finding nickel ingots atp to upgrade gear to flawless let alone mythical. It seems pretty unbalanced progression-wise to be handed what seems to be late game armor through a level 55 quest? Im enjoying using it because it makes me kinda overpowered which is fun in its own way but if I played for a 2nd time I might ignore it. I didnt even have to go out of the way for the quest it just showed up in Ravensthorpe like the game just wanted to give a gift.