Important Concepts in Economics

The following is a list of important concepts that any econ (especially micro) course should be built on:

1. Opportunity Cost
2. Optimal decision making using Marginal Cost and Marginal Benefits
3. Specialization leads to better standard of living (comparative advantage)
4. Incentives matter
5. Invisible hand works but sometimes it breaks down (market failures: externalities, public goods and tragedy of commons)

Could a course be built around these five concepts?

I mean giving these 5 points to the students at the begining of the course and as I teach the course ask them to connect the subject with one of the 5 points. Supply and Demand are basically Marginal cost Marginal Utility curves. Economics profit vs. Accounting profits when teaching Monopoly vs. Perfect competition ties in with opportunity cost.

I have not thought this out all the way but it could satify student thirst for specifics at the same time converting them to the dismal religion of economics.

Did I forget any other concept? These are the five I usually cover. Have I forgotten any other? Should I cut this list down (5 concept is too many)?