That sounds like a great idea, but I don't know if it is possible to atomize a monopoly bonus like that
Some things to say about this UB.
First, as you surely have noticed, "entrepôt" is a French word. Using a French word for a building meant to symbolize the Malian/West Sahelian region will appear as quite colonialist.
I've been searching a bit in a French/Malinke-Malinke/French dictionnary written by a missionary in 1906 (you can found it
here) to see if a word with a similar meaning can be found (there is a chance that this dictionnary is unreliable, but this is the only one I've found with that much vocabulary).
The only word I've found for now is "
Karfa" (page 89), translation of "Dépôt" ("deposit") but it's more a designation for the objects within than for the building itself, as the dictionnary indicates. There are also the words "
Sigiula" or "
Daca" (page 98), translated from the French word "Étape" (that can be translated into "station" in English, with the meaning of "place where you stop, escale").
For the building itself, here is what I have in mind after all the discussions we've had.
Name to be determined
Caravansary Replacement
200
unlocked at Currency
+1
Gold +2
Culture (up from + 1

Gold only)
When a Land Trade Route originating here and targeting another Civ is completed, receive a Tourism boost with the Civ based on your recent Culture output.
Land Trade Routes gain +75% Range and +2
Gold (down from +3
Gold)
Trade Routes with other players to or from the city generate an extra 1 Gold for the city owner and an extra 1 Gold for the Trade Route per Luxury monopoly
=> This bonus is taken from the Colossus WWonder and is initially weaker, but scales with your number of Luxury monopolies.
+ 3
Production for each Strategic monopoly
=> so for 25 % possession, no bonus for global monopoly for strategic resources, for they'll already give great yields
+1

from Merchants.
+1

/

for every 3 desert, or tundra tile worked by city.
Truffles +2

Cotton +1

/

Furs +1

/
This way, the more luxury monopolies you have, the more your cities become attractive to foreign trade routes, and the more you gain in taxes. The UB will initially bring a bit less gold than a Caravansary, but it has the potential to be far more rewarding if you play well.
New Mongolian Yassa Court
available at Philosophy
200
Production Cost
can be built in non-occupied cities

Production Cost is slightly increased with number of Cities
Removes

Extra Unhappiness from Occupation
+2%
Production towards Military Land Units in all cities (Range, Siege, Mounted and Armored)
-1%
Distress, Boredom, Illiteracy, and Religious Tension in all cities
I agree with adan_eslavo : the idea is interesting, but it could scale way out of control (imagine -40 % Distress, Boredom, Illiteracy and Religious Tension in all the 40 cities of a mega-empire : the happiness benefits would be far too great). One solution could be to put a limitation (like, +30 % Production, -20 % DBIRT), but I am not very satisfied with this (it would mean that the new YC is far weaker than the old YC for most of the game for finally being only a little better at the end). Another solution could be to make the building give a bonus scaling with the number of annexed/occupied cities (so cities you've settled won't count) so that the scaling requires a bit more risk-taking.
Rome gets +2% gold from city connections globally per colosseum.
Yes, but percentage of gold is far less important than percentage of production and unhappiness reduction (which gives bonus to all yields).
First, thank you for having modified the scaling. I've done one game, and it feels way more on point.
One other problem with this this building (I don't hate it, I swear) is that it gives a global yield (science) that won't be taken into account in the city production but it is however required in any city in which you want to make a faith purchase to be triggered to build a Madrasah beforehand. Because of this, every missionary/inquisitor bought in a city without a Madrasah is lost science, and it seems wrong to me that a bonus meant to bring a specific kind of global gameplay to a civ is only available in specific cities (it just makes you create religious units in the heart of your territory instead of in the extremities where they are needed for conversion).
Because of this, I would be for scraping the Madrasah and giving Arabia a UW replacing the School of Philosophy. Something like this :
House of Wisdom (replaces School of Philosophy)
Available at Philosophy
135

Production (cost scaling with number of cities)
+5

Science +5

Culture
+5
Faith
+2 Great Scientist Points
and +20 % GP generation in city
+20%

Science
and +50 %
Faith in the city during

Golden Ages
15
Science on
Faith Purchase, scaling with era (increased to 75
on Great Person
Faith Purchase) => Global effect
2
Great Work of Writing slot (+3
Science +3
Faith when themed with GWW of the same era) (up from 1 GWW slot)
This would only come one tech tier before the Madrasah, at a time when there isn't as much faith as in the Medieval era (the player will begin to build the Temples/GTemples which will allow to regularly buy units/buildings), so I don't think it is necessary to tone down the science bonus.
There is a bit more synergy with Tradition and Artistry here, but it's only a drop in the sea, seeing how much synergy Arabia already has with these two trees.
This is also a way to make more references to Harun al-Rashid, since he is believed to have built the HoW as a library for his collections.