A couple more ideas:
- could be nice to have it calculate and show the score of the word you have currently placed
- when you place a tile on the DL or TL you can't see where the DL and TL are any more (I think on Scrabble board they have little triangles that stick out past the edges?)
- I found myself wanting to know the 'target' score, but I guess that would change the experience a bit