As for the Kapitain, what do you think about him giving the supply promotion to adjacent naval units for one turn? It's not a direct combat buff, but helps in prolonged naval campaigns and gives your fleet staying power far from home. This would fit well for a non-aggressive civ and would help the diplo game. I'm thinking of liberating and protecting distant city states or hunt distant barb camps for quests. And it would fit a civilian captain and explorer, bringing his logistical skills to the war fleet.
OK, I will implement this in the next version.I was musing along the same lines, but didn't have it nearly as clearly in my head. This is faithful to the historical vibe, and a useful trait.