I used this sheet for the merc troop trees and therefore all "differences" I may mention are only valid between this troop tree and the 605b Version.
https://docs.google.com/drawings/d/1rmebMy6lHmzGSmGDDi9QxpWF2DGzm7IZIoKIk2TEFE4/edit?hl=en_US
First of all: I love this mod, I only took so much time to orderly find out and write down bugs with troops to help you guys, not to piss anyone off.
First a few comments to Vaegir troops:
the basic bowmen all have crossbow instead of archer skill:
Vaegir_Bowmen: crossbow <-> archer
Vaegir_Archers: crossbow <-> archer
Vaegir_Marksmen: crossbow <-> archer
Vaegir_Master_Bowyers: crossbow <-> archer
The basic melee troops also have a weapon setup that uses shield and single weapons, so they could all use some 1h-skill
Vaegir_Varangians; single Hand 60 -> more?
Vaegir_Veteran_Varangians: 60 -> more?
Vaegir_Varangian_Guards: single Hand 60 -> more?
Vaegir Pikeman often uses a bardiche (2h-skill) but has of course polearms skill
The Vaegir_Linemen has a shield and either a one handed or two handed weapon. As he is the follow up of the pikeman he lacks the skill to use both. A spear would be nice for shield and spear. Or whatever you want him to be. Just give him weapons suitable to his polearms 180
and perhaps rise one handed skill for his sidearm.
just to be as complete as possible: The ivory bowman often has no bow (already known)
Now to the mercenaries:
Male Merc tree:
Merc Rubble has a bow but no skill to use it.
Merc Runner is is now called Merc Stablehand
Merc Cavalry can have a lance but has polearm skill 30
The ingame-troops differ from the Merc tree on the sheet. It is now: Watchman -> Guard -> Swordsman -> Zweihander
Merc watchman and guard have two handed skill but only spears
Merc Swordsman has only 75 1h-skill though he always carries sword and shield
Merc Zweihänder has sometimes an arbalest and sometimes 1h+shield (too low 1h skill) and no(seldomly?) 2 handed weapon
Merc Trained Crossbow always has a bow (switch with Huntress?)
Merc Veteran Crossbow always has a bow (switch with Master Huntress?)
Female Merc tree:
The troop tree sheet misses the shield maiden, but stats and equipment of all female riders look OK. The shield maiden is introduced as infantry troop instead of cavalry (not a problem for me, but perhaps for AI?)
Camp Defender has a bow, but crossbow skill 60 (switch equipment with tracker?)
The "hearth warrior" from the sheet does not exist anymore, it is now: Pike Sister -> Pike Maiden -> Line Sister -> Line Maiden
Merc Line Sister always(?) carriers a Voulge (2h-skill at least for player) but has polerarm skill
Merc Line Maiden always(?) carries a voulge (2h-skill) but has polearm skill
Merc Tracker has Archer skill but a crossbow (switch equipment with Camp Defender?)
Merc Huntress has a crossbow instead of a bow (switch equipment with trained crossbow?)
Merc Master Huntress has a crossbow instead of a bow (switch equipment with veteran crossbow?)
Merc Stalker has a crossbow instead of a bow and is typically a infantry troop, maybe suboptimal for AI
Hope my field studies help you and I really hope I did not miss anything so all mercenary troop things are mentioned here in one post.
i have a companion at level 19. thought he was at 20 so i didnt bother checking 
