Role Playing
The world building rules are meant to help you role-play - not in small scale day-to-day actions, but in the way your character behaves in the longer term. Using these rules you can build towns, businesses and organizations that follow your character's personal philosophies in the way they do business, the way they treat their citizens and in a number of other, broader, ways.
These are a few examples, but that you are not restricted to one section of rules, and that you can have a range of holdings and investments. Build the portfolio that suits your character - and don't be afraid to mix it up.
Traditional Fantasy - The rules are designed to replicate a fairly traditional system of benevolent nobles who care for their citizens. The core structure is pseudo-feudal, with every-day folk owing allegiance to their lords, who owe allegiance to senior lords … That makes for a comfortable TN setting for a campaign game, with all the 'baddies' as enemies :) However, by manipulating the balance rules you can build Lawful and Chaotic holdings, and by RP decisions you can control Good and Evil …
Fantasy Democracy - Not the one person, one vote version that we think of as democracy today, but an earlier system that gives a vote to selected members of the community. Traditionally, the electorate is made up of nobles, aristocrats and wealthy individuals - but all the PCs should fall into that category, before the game has been running for too long. In The Stolen Lands game, I use a 'chivalric' order to control who is eligible to vote - although, as it is a multi settlement game, there is also a residency qualification. Think medieval city burghers …
Capitalist - The core concept behind the Business and Merchant rules. The more money you have, the bigger, better businesses you can buy - and the more money you can make. Strong hold owners will, of course, push you into following their own political strategies - so you might have the opportunity to invest in Good or Evil aligned settlements. Your character's personal alignment, and philosophy, will inform your investment decisions.
Green - Rangers, Druid, some Clerics and other individuals might be followers of 'The Green Way', or a similar philosophy. Build, or invest in, wilderness or rural holdings. Green strongholds tend to be larger, more spread out and often generate less status than cities - just as in real life settings.
Religious - The rules are primarily designed to allow Priests to build a religious organization that covers one, or more, strongholds - and the PC might, eventually, be able to claim the title of Bishop, Abbott/Abbess or High Druid. However, they aren't restricted to purely religious developments - a cleric of Abadar may well build markets and a bank, a cleric of Erastil might establish a rural travel network and a priest of Iomedae might have a castle or other defensive buildings. Be inventive, but stay within the deity's published portfolio of interests .
Community - There is a selection of 'Community Developments' that produce less profit, but provide better facilities for the everyday folk of the holding - some don't provide any profit at all. I don't think that you can build a whole settlement with Community Developments, but they can be used by councils, stronghold owners and business people to add a socialist element to their Role-Play. A community development is still owned by the PC, but they consciously take a smaller profit so that the whole community gets more benefit from the development. A PC with strong socialist tendencies can combine Community Developments with Civic Developments, and might add some Charitable donations as well.
Charitable - A charitable PC makes donations to good causes - although the good causes are defined by the PC's personal philosophy. However, to be classed as Charitable, the donation must be over and above any requests from the local rulers, and there should be no real benefit for the PC. Examples might include building an orphanage, or a copper School, or it might be setting up, or making a donation to, a non-profit organization. Three Ladies Schools, for example, was set up by donations from three nobles to build Public Schools - the schools charge and make money, but that money is invested back into building more schools. None of the nobles get any economic return from the schools. On a smaller scale, a PC could sponsor an education for a named individual NPC, or even set them up in business.
Cooperative - Cooperative developments are owned and managed by the community, for the good of the community. They might arise spontaneously, or be created by a charitable donation from a PC. Once the cooperative has been started the PC loses all control of their donation, and any income is controlled by a Community Leader, who might be a low level commoner, and is always an NPC under the DMs control. Most cooperatives spend their income on extra community developments, although they may branch out into civic developments if they think it is appropriate. In rare cases, the Community Leader might be asked to take a place on town council, but strongholders should be aware that the Cooperative will have its own agenda.