One of the "issues" is that the gear is from such different periods. I'm not an expert, but I was led to believe (from reading Bernard Cornwell books) that the big polearms and two handed weapons of history were invented to deal with--i.e., bust through--plate armour. As fun as it is to shout "shield wall!" in cRPG, I thought shield walls were pretty much a Dark Age thing, because once people had heavier armour, you needed both hands for your weapon, more than you needed a board to stop you from getting stabbed through your leather or shitty chain or whatever.
In other words, balancing the game and realism are entirely opposite objectives. We could all just go play Vikinr, I guess...