The Sutton HOO helmet is from the Anglo-Saxon period and although very cool has technically no place in this game, since its a few hundred years short (600+AD). Further more even if some one would have worn it. They would have either been royalty or a wealthy officer, So not whole units would have worn them. Same go's for the golden ridge helmets, only the most wealthy. Actually 80% of most units would have been without helmet, since most would not have been able to afford them or would not have went on raids yet. And those that could afford one, had it made out of iron. Or had it passed on to them thrue the family lines. Same apply's to armor. Leather armor is actually the same and constant you can be assured of. Its light, cheap, and easier to make them armor out of iron. Most units would have worn either leather armor or thick padding. Those that would have worn chainmail, more then likely took them from the body of there foes in the raids against other country's, since they may not have been so lacking in the creation of iron armor. Same applies to lamellar armor, whether it's the full iron one or the half leather and half iron. Sure you might think there is no evidence, but there is if you not only look at how other nation's did it, but also take into account that vikings where raiders and there for other then there weapons and simple leather armor, would have gotten most stuff on there raids from other nations. So if you want to make historical accurate units, then technically you would have to keep the variation in them, that not all of them had the same things. Meaning one officer and then a band of rebels with swords and axes and short spears. then a unit with long spears and sword and axes, a unit with bows with swords and axes, Horse unit with sword, axe or spears. Each units diversed in armor aswell. And different kinds of ridge helmets or Norman helmets (meaning without the ridge), along with no helmets. But ok all just my opinion and i look forward to seeing your mod in the future.