I settled on the following for endgame scoring, at least for a first try:
Things I like about it:
* Good distribution of word sizes: 3/3/4/4/4/5/5/6/7/8.
* Uses all letters of the alphabet.
* Reward (letter count squared) increases a lot as the word length increases.
* Largest word is 8 letters, worth 64 points - no scoring 170 or 200 points off a really long word!
Things I don't like about it:
* Not thematic or at all related to the game. I thought about using
But that (a) doesn't use all the letters (and would therefore require me to remove some of the City Tiles, and there might not be enough left) and (b) Doesn't have a good distribution of word lengths.
* Not a lot of overlap - many letters (even "common" letters) are only used in 1 word. I think the City Tile distribution would need to change to reflect this.
I hope to get a playtest of reading Railroad in tonight and see how it goes now with targeted goals and proper (?) coin rewards for words in-game.