Fyrdmen could have shields as well as spears, and high pierce armour to represent the shield wall. But then I guess they’d end up similar to either Eagle Warriors or the Lithuanian Spearman-line.
I’m not sure about Housecarls. On the one hand, they fought at the battles of Stamford Bridge and Hastings, both of which are actually in the game already (and that’s precisely why they’re relevant to this thread). But on the other hand, they only existed towards the very end of the Anglo-Saxon period (for less than 100 years), the most famous battle they fought in is one they lost, and their name is just a different spelling of a unit that already exists.
(Also, I don’t actually think they should add Anglo-Saxons…)