Ability to choose options when starting a new multiplayer game.
Game master chooses options, invitee reviews and accepts/declines.
For example, i´d like to be able to disable bombs, toxic tiles etc, or simply have the game place them invisibly now and then so that whoever runs into it gets it. Great to keep it neutral, so that the bad loosers can´t really blame you

And maybe cooperative mode?
Themed? Custom languages/dictionaries in klingon and norwegian?
5 letter words minimum-option? Alot of the 4-letter words are just 3-letter words in plural form, +s.

Another suggestion : a tile that chooses a random letter for good or for bad. It ought to flash and go through the alphabet before it settles on a character. If you`re lucky, it could land on a 3x multiplier, if you´re unlucky you just get another malplaced consonant.