Hey guys, I just had an Epiphany while writing some of the subjects.
So keep a look out on the edit date on the posts to see which are update or not.
My epiphany actually was the spotting of a major flaw on the commerce focus subject, specifically how buildings could work with the investments rates.
Let's say library as basic example:
instead of the +25%

in addition to the

output of the city, I suggested:
+1

/5%

rate (figurative numbers for demonstration)
The flaw in here is that it doesn't matter whether the city is expending 100 or 10 of

in

, the output of the library ends up being the same, and that's not in harmony with the concept I attempt to achieve.
So I brainstormed for solutions, and came up with:
1° - +1

/1

, then if you got like 25

spending on

you get a output of 25

total
2° - +5%

/5%

rate, which is like a middle term result and increases considerably with investment
Now, the second one is considerably closer to the actual output of recent games, the difference with more investment the output increases drastically, increasing the research rate will both increase the original output and the rate multiplier of the output. Thanks to my Calculus skills, I've been able to figure out the result is a square equation, greatly increased in function of the investment variable.
The first solution however, stays more in harmony with the concept itself. The output is directly proportional to the investment. The initial output is greater, but as investment grows, it stays proportional to the investment rate.
Comparing the two, the total output of the second will always be lower than the first, only equalling when investment reaches 100%.
The Second option also makes more sense when comparing to other investment types, such as

to

, the output of those buildings will always be direct proportional, not the square result of.
To compensate on the surplus output, I've revived another idea, to have a variable tax to the empire, that is: from the overall

extracted only a portion of it is actually used to public means, citizens can now get a life of their own.
So I need for people to give your opinion on this changed idea.