Disclaimer: i'm not responsible for damages to your city files (or any other files, you computer, your mind) due to the use of my scripts, use them at your own risk.
SIMCITY ADDITIONS
The intentional idea i borrowed from a MS-DOS program named "EDITCITY" with which you can change certain values in SimCity city file. EDITCITY allows to change churches and hospitals to either an empty residential, a high value high density residential or a high value high density commercial. You can of course change the amount of cash and the tax rate. Further EDITCITY can alter the values for residential-, commercial-, industrial population, crime- and pollution ramp, the latter five values are dynamic and will be changed as soon as the game runs though they have little value and i don't care about them here. Also you can change the external market size with EDITCITY.
A few thoughts to the "external market size", the manual describes this as a variable which will raise with the growth of your city but this isn't the case no matter how big or how old a city is this value stays as it was stored at beginning of the game. MS-DOS SimCity stores here a "6", Amiga SimCity stores a "4" and both TerrainEditor store a "4". After i experimented even with rediculous high values like 0x7F i came to the conclusion that this must reflect something little else as one can guess by the description in the manual. I assume this reflects the connectivity of a tile. You might know that SC2K shows a connectivity from 1 to 8 for each tile personally i assume a "4" is following connectivity 1,2,3,4,1,2,3,4... with "4" as 100% connectivity in the same manner as in SC2K thus a 6 will result in 1,2,3,4,5,6 with 6 as 100% connectivity, this would at lest explain why i don't experienced noteable differences if i changed this value. Nonetheless for all my generated terrains i used a value of "7" whatever the cost might be Still i'm not sure here what exactly it reflects but a growing market size it can't be this is obvious since this value never changes.