General/Specific
The more general a model is, the more it can be applied to a wide range of situations. However, the more general it is, the less information it supplies about specific situations. E=mc2 is understood to apply to the entire universe, but it doesn't tell you how to make a match or how to build a pump. More limited and specific models can provide more detailed and useful information. One important element of any model is to know the scope of the domain that is usefully described by it. For example, NLP is a wonderful model, but it is not directly useful in designing an automobile engine or telling a doctor how to set a broken bone.
