[@Torack]

Kalam is a good name choice, one of ym favorite book characters. 

As far as the weaknesses, I think you need another. One that is more physical, like if he's big, then is he slow as well. If he's small, is he not as sturdy. Does he have bad eyes. 

Currently, your weaknesses are more situational. After rthe first off hand mention, the party isn't likely to mention your dad again, and in face of the enemy, they likely won't be asking him about family history. Drinking is okay, but chances are you won't be getting hammered pre battle