I’m not familiar with the default setting for ACKS, but I’m not sure about the proficiencies chosen for some of the barbarian types, in particular for those from Jutland. Maybe you were trying to model off of Conan (since he does a lot of climbing in his tales as a thief), but couldn’t Seafaring or Running be better options for a culture at least loosely modeled off of the vikings? I say Seafaring or Running would be better because to me those are more core to the vikings use of ships and hit and run tactics. As for the Climbing it seems to me that Mountaineering might be a better fit than Climbing.
Similarly, while I can see Precise Shooting as a good choice for the Skysostans, wouldn’t Riding be a more fitting choice?
Perhaps Natural Proficiency could be opened up a bit to where the player could choose 1 out of 2 or 3 different proficiencies appropriate to their native culture? Something like:
Jutland - Climbing, Running, Seafaring
Skysostan - Animal Training (horse), Precise Shooting, Riding
Ivory Kingdoms - Ambushing, Mimicry, Running
Again, I’m not familiar with the default cultures of ACKS, but I think by opening up the Natural Proficiency up to a choice of 2 or 3 you can also prevent an overly strong stereotype from developing. Perhaps not absolutely all Jutlanders are good at climbing and one’s character can stand out by not being good at Climbing while still being a Barbarian?