One of the little tricks I am happy to share involves captains. I see posts frequently about having to deal with poor ones. You do not need to use them.
Here is the trick: the game always has two new captains in the tavern each day. So, when you find a poor one, like the 0/0/0 class, hire him on a surplus snaikka, and send it to an out of the way river town such as Novgorod or Cologne. There, fire him. You can send multiple captains to the same town. I have stacked up over twenty this way before. The game in random generation of captains will produce better ones which you may hire and keep. Better to hire a 5/3/4 and train him than the 1/1/1.
Now, there is a bit of finesse for the trick as well. If you also hire the good captains, you can similarly save them up in a river town for when you might want them. The last fired is the first one you can hire. If you have several ships in town, you may shuffle the deck, and stack them up in the order of best captain avialable first by hiring them, and firing the worst one first, and the best ones last. Similarly, you may also leave the poor ones in deepwater ports for the AI to hire. I just prefer to monopolize the supply, and that is why I isolate them.
Occasionally the game will spawn a new captain of course in whatever town(s) you are using. You may need to shift him to the appropriate place, there to spend his days playing whist or shooting craps, and carousing with the barmaids.
The game doesn't count the fired captains, and keeps on generating new ones. I don't know if they count in the population, but perhaps you could load a few hundred in the tavern and see if there is a boost in your city population for the contest games, ha ha. I will leave that for the more adventurous souls to try.