Most yield income is very low numbers, such as 1

from tiles adjacent to rivers. Since decimal improvement yields are not possible, we cannot adjust incomes, and must have the 3=3=3 value ratio I posted earlier. Most costs are very large numbers so there's a lot of wiggle room (200

to buy a scout). This means we
can change expenses and rewards from those expenses.
6

>>> 2
I got this from 2

= 2 artists of 3 culture apiece = 6

. However, culture is an unusual exception to the above rules because there's few sources of it from terrain. This means we could set artists to 2

, in theory. The problem is the psychological effect it would have. I strongly suspect most people would infer artists are less powerful than other specialists if this change were made, since all the others give 3 yield and artists give 2. This might revert back to the unfortunate situation in vanilla where everyone avoided artists.
This is why I aim for equality between the major yields. In game design psychology is more important than mathematics. The perfect example is the spearman-vs-tank situation. People almost universally felt frustrated when we lost battles with 98% chance of success. Our mind inherently rounds up such situations to 100%. Another example is things like the Great Lighthouse can be mathematically very powerful, yet be perceived as very weak, as
demonstrated here on the City Development thread.
On a side note... this is why back in 2010 I seriously considered scaling up all yields by a factor of 5. If everything was 5 times higher we'd have a lot more room for adjustment. Or alternatively... if we could have half-yields on a tile, but that would require the game core only Firaxis has access to.
