I took a guess that the last title is 60 cities, 90 towns, and 120 villages. I did some rough calculations based on those numbers.
To build a city you need 80,000 wood for houses and say another 9,000 for farms and storage towers (assuming you put farms into every settlement).
Time to build settlement 14 days set.
Time to build storage and farms 14 days minimum set.
Time to build 2000 houses (guessing an average of 30 days)
Assuming you can chop around 1200 wood per day (includes movement time) 75days.
Total time to build a city will be roughly 5 months, times 60 cities is 25 years spent building the cities.
To build a town you need 20,000 wood for the houses and say another 6000 for farms and storage towers.
Time to build settlement 14 days set.
Time to build storage and farms 14 days minimum set.
Time to build 500 houses 7 days average assuming you have enough people in your expedition.
Same 1200 wood per day is another 21 days.
Time to build a town will be roughly 2 and a half months, times 90 is roughly 19 years additional.
To build a village you need with farms you will need around 5000 wood minimum.
Time to build settlement 14 days
Time to build farms and storage towers 14 days.
Assuming you don't build any more houses (or you build a few more with the farms and storage towers) no more time
Same 1200 wood per day is another 4 days roughly.
Time to build a village is a little more than a month, so you have another 10 years.
Minimum time spent just building would be 54 years, if my guess was close, and assuming you actually want someone to obtain all 8 titles.
I don't know what planned improvements will cut that time down, but you might want to consider reducing the requirements for the last two or three titles. Before you posted the requirements, I had guessed that it was going to be:
Marqués: 5 cities, 10 towns, 20 villages
Duque: 10 cities, 20 towns, 30 villages
Virrey: 20 cities, 30 towns, 40 villages
and then 30 cities, 40 towns, and maybe 60 villages for the Viceroy title...but that was just a guess and I had guessed a minimum building time of about 30 years under current game conditions.
EDIT: That doesn't even consider the population growth needed, but I thought that the growth would take care of itself once you had enough buildings.
One thing I should add though is that it is taking me nearly 20 years game time to get the first city, and most of that building would take place after that. That would mean around 70 years of game time for the current requirements under the current conditions. I focus on building the first settlement by making trips to Palos to "purchase" colonists and add those to the growth. The twenty years does include building enough capital to purchase those colonists and the extra ships and the military needed to "encourage" trade with the natives to increase the capital.