As well as the single building mode, where you click and place a building, then the pointer returns to normal, I'd like there to be a mode for building that keeps the currently-selected type active, so that there's no returning to the menu to get additional buildings. This would be particularly useful for fields and wells, but some people might want to do chains of other buildings as well.
One method would be similar to the tools like format painter in Microsoft Word: single click applies once; double click on the tool applies until you click the tool button again or press escape.