Well, there's been dev diaries where the developers have talked about Balance - which is one of the LAST stages of game development, typically. The last one recently mentioned this, actually and I've quoted it below.
[quote author=Paul Kaloff, Source: https://www.taleworlds.com/en/Games/Bannerlord/Blog/97 ]
WHAT'S THE MOST DIFFICULT THING THAT YOU SOLVED SO FAR, DURING THE PRODUCTION OF BANNERLORD?
“Tackling the task of balancing multiplayer. There is such a broad variety of weapons and different classes, each with their individual perks, that keeping them balanced can be quite challenging sometimes. Each faction, as well as, each class within that faction, should have their individual advantages and disadvantages, which need to be evaluated. It's certainly a buttery slope if you change one thing you affect basically everything else.
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