As far as I've understood based on the eps so far, the mental models were created to understand the edge humans have in naval warfare, bar the pitiful technology. As soon as humans, Gunzou to be specific, got to captain the I-401, he has been constantly beating technically far superior foes. I reckon that's essentially what the mental models are supposed to figure out. Kongou stupidly thinks she has humans all figured out already, but the rest don't seem to share her optimism (with good reason, after getting their assed handed to them by Gunzou).

So, the mental modes obviously need to be as human as the Fog could create them. Some of the stuff we have seen is extremely easy to program in, like vocabulary. But that doesn't mean they can use the vocabulary in innovative ways like humans. Or basic emotions, but that doesn't mean they can use and express those emotions naturally when interacting with others. I guess the mental models that really have been in contact with humans aren't anymore interested only in warfare like mere weapons are suppose to be (according to Kongou).