Ok, I figured out the answers to some of these with testing (though not all). Here is some info:

2) Lifeboats do not seem to affect amount of cargo recovered when capturing ships (so just salvage from destroyed). Took over a light galleon 6 times with lifeboats, 6 times without, and the with lifeboats only recovered an average of 4% more cargo (which I attribute to random chance). This was with the suttler trait, so not sure how things would stack and whether I would expect a 20% or 10% increase, but it seems like it doesn't happen.

3) fractional speed upgrades do work. So even if that 10% speed upgrade doesn't show a difference in the listed number in the shipwright, it will still make your ship go faster (tried this with a light galleon, with or without an upgrade it was speed 17 in the shipwright, but with the upgrade actual battle speed went from 23 to 25 as expected based on percentages since it was a 10% upgrade).

4) Higher absolute number of crew does not seem to affect cannon reload speed, instead it seems only based on percentage of your crew available (whatever the max is). So 84/84 crew on a light galleon outfitted with crew reducing upgrade is the same reload speed as 140/140 crew without those upgrade (using powder boxes to replace the hammocks bonus in that trial). Boarding party diffeence is of course small

5) still uncertain. I know letters of marque cancel quests with other nations though. Something interesting I had not realized, but you can get two letters of marque from same nation against different targets even when your rank only allows you one letter of marque, so long as you destroy one fleet of the enemy inbetween the first and second letters. Makes sense, so the limit is on number of nations you work for, not targets for a particular nation.

6) Looting skill does not affect cargo recovered from captured ships.

I still haven't figured out 1) and 5), so if anyone has any thoughts.

Thank you for the testing! I also struggle with the nun mission as you don’t get any melee weapons so there is practically no way to defeat the guards. I guess using a fast character with good combat stats may help, as you could run away-reload-shoot-run away, but that’s a speculation

Originally posted by AzureSamurai:

Thank you for the testing! I also struggle with the nun mission as you don’t get any melee weapons so there is practically no way to defeat the guards. I guess using a fast character with good combat stats may help, as you could run away-reload-shoot-run away, but that’s a speculation

sounds like the usual mount and blade cheese missions

part of the fun and frustration lmao