I'm sorry I missed your request for ideas and the update, I'll give it a whirl and get back to you.
I've also got even more respect for what you've pulled off after spending nearly all day trying to implement the force_weapon script into P&B+Diplomacy+PBOD. I swear, my attempts at module system editing are driving me mad.
On the topic of ideas for the Nord tree, I actually spent most of yesterday evening researching the Anglo-Saxon professional and semi-professional soldiers the troops are named after. I've got equipment lists for most of the troops based on second-hand interpretation of historical texts which you're welcome to if it interests you at all.
My main problem with the Nord tree was that it was a bit of a one-trick pony - axes, axes and more axes - which wasn't really either practical or culturally convincing. Thrown weapons were typically "javelins" (though the term then meant something more like the war darts in game) and the main weapon carried by all fyrdmen was a spear, maybe with a sword as a side-arm.
Huscarls (and, I think we can assume for this purpose, Thegns) might have had a spear but certainly weren't required to, as were the fyrdmen. They were expected to own a sword (a very fine sword, according to the texts - something about hilts inlaid with gold) and shield, in addition to their mail and helm, but the weapon they were known for was a 2-handed axe. The information I found also specified them as the ones known to carry the javelins.
The men making up the armies all seemed to be expected to have a horse but only for the purposes of travelling, not for fighting upon.
There aren't really any historical troops I found mentioned as skirmishers but lithsmen and butsecarls were talked about as specialist ship's crews who were often hired as mercenaries. It seems they didn't fight literally at sea but would almost always drive their enemies to the shore and fight there. Given that they spent most of their time aboard boats it seems likely they'd wear armour that wouldn't drag them immediately to the bottom, should they fall overboard, and carry a decent supply of bows or javelins to harry opponents which makes them a reasonable point of inspiration for the skirmisher line.
There was also a brief mention of the sort of weapons used by townspeople forced to defend their homes (a good start for the recruits) but the list is, unsurprisingly, just tools of their trades pressed into service as weapons; hunting spears, hunting bows, wood axes, knives etc.
Sorry for going on at such length, I'll get back to you about the adjustments.
EDIT: Oops, one last thing I forgot. Part of the issue facing down cavalry was the horse stats; I assume you already know, and have a reason, but you've got native horses rather than Aeon's P&B versions which makes an immense difference.