Don't forget to build enough houses for your settlers. Having a firm roof over your head does wonders for the attitude. The contentment of your settlers, or the fulfillment of their wishes, is your guarantee for the commercial success of your settlement. When the inhabitants of your island become unhappythey sometimes leave, which then leaves you with both not enough workers and too few taxpayers. You can always see how satisfied your settlers are by clicking one of your houses in the info mode.

The facial expression of your settlers gives you an idea how satisfied they are. Tax rates, the availability of food and consumer products, and the public amenities available to your population all affect the level of satisfaction your citizens enjoy.
You can adjust the tax rate by using the slider. Keep in mind the current economic situation when setting the tax rate. High tax rates over a long period of time have a negative effect on the satisfaction of your citizens. You can use this as a short-term way to generate extra income. The symbols underneath the slider show what the people in your settlement currently desire. Placing the cursor over one of the symbols shown will display more information about it in the info bar. Beside these symbols you can see a vertical bar. This shows how satisfied the people in your settlement currently are. The horizontal black line across this bar represents the minimum level of satisfaction for the current level of civilization. The higher the red bar climbs, the more satisfied your citizens are. The tax rate also has an effect on this bar: the higher the tax rate, the higher the black line. The higher the black line, the more likely your citizens are to become dissatisfied. The horizontal bar shows the level of the food supply. Again, the black line shows the minimum standard necessary. Having enough food to go around is absolutely necessary for the satisfaction of your settlers. You will only attract new settlers when those you already have are satisfied. An increase in population is one of the main conditions for the advancement of your settlement to the next level of civilization.
There is a total of five levels. Level 1 consists of pioneers, level 2 the settlers, level 3 the citizens, level 4 the merchants, and level 5 the aristocrats.
Each time you reach a new level of civilization new buildings become available, and the needs and desires of your settlers grow as well. It is easy to see when you have reached a new stage of civilization because, as long as there are enough construction materials on hand, the houses automatically increase in size. Don't forget to build more houses to attract more citizens.