The best move has the highest possible score, but it is also the one
leading to the most interesting game. This is a subjective notion, but
some heuristics can help, such as:
- a move sparing a blank is better than one using it
- a move with many prefixes and suffixes is better than one without
extensions
- a move "opening" the game is better than one blocking it
- a move leaving a nice rack is better than one leaving "bad" letters
At the moment, only the first heuristic is implemented.
