My suggestion to a rework of work hours, are based on how the workforce are in real life, I’m not basin this on an economy that use slave labor, this might in some cases have been used in the Caribbean at this time, but its political not accepted for some reason^^ also in this case we are generally talking about trained labor.
In real life a city would have a certain amount of inhabitant and therefore labors, if a city had 5.000 inhibitors then maybe 1000 of those would be people whose work we would be able to use for shipbuilding and manufacturing. Those would work 12 hours a day so that would put it to 12000 labor hours a day that we can use in this size of city.
This number as it is are static, nothing will change that right now( a mechanic to increase this we can put in later and I will take it up further down)
With a static number of work hours on the marked, we can now start to give those workers a job as a major shipyard I need his service so I’m offering him 50 cent an hour this would be a fair price I thought but the labor don’t need to take the first offer he gets he actually got a whole day(indgame time) to decide on my offer, and in this time a competitor will be able to place another offer for the workers labor. The competitor has in his offer said he wanted to pay 80 cent for x amount of hours, if more labor hours are available I would then get what I could of my offer, so I would get x amount of labor hours for 50 cent, but if enough competitors had put offers in better than mine, then I would not get a single labor hour, because i clearly were too stingy with my coins.
So in a town with a lot of competitors the price of the labors would go up significantly, so the price for producing stuff in this city would increase and so would the sell price of ships and other produced items. So as a stingy merchant that would rather sail 1000 miles then to pay those greedy labors a fair salary I change my production city to a small local community on the other side of the world, the community might be only 500 in size but I got all the labors for myself and can now offer my low salary to those wild people and they will take it(maybe not with a smile)
Back in the large city the price has gone up a lot ( not all are as stingy as me) and it is known all across the ocean that in this time you as a labor can earn a good living, so workers start to move their family to the big city and so the amount of labor hours slowly increase, but only up to a certain degree, you can only press so many people into the same amount of space, so to increase the size further the lord protector would have to build and in other way expand the city and this will for every expansion become more expensive.
This in my opinion would make a lot more options in the game variable.