Money is very important near the start of the game, as early buildings can accrue a lot of advantage. Choosing the Trader or Prospector for 3 or even 2 total coins can be a powerful move early in the game.
Try to pick roles that are better for you than everyone else - i.e. the Builder when you have the most money, the Trader when you are the only person who can sell, the Mayor when there's an uneven number of colonists, or the Captain when your opponents have goods they want to sell.
- The Large Warehouse is the least used building in the game, there is little merit in building it, at least in games where you can rely on the small warehouse instead.
- The University is effective in the last round, if you build a large building and there won't be a mayor to activate it.
- The Guild Hall is generally the best large building, it almost guarantees 7-8 points and 9-10 points are possible. The others can't reach more than 7-8.