Please consider words that can be split into two parts each complying with one of the above structures (i.e. a-z or z-a ).
Those parts need not (but preferably may) be valid English words.
For each of the above 4 classes provide a word with maximal score, as defined below:
1. Each letter gets its matching number: A is 1, B is 2, ...Z is 26.
2. If both parts consist of actually existing words double the words values.
3. The sum of the four results is your score.
Example: BOX / WOOD = 2*(2+15+24+23+15+15+4) = 2*98 = 196
Go get the highest value!