Maybe putting down a tile should open the dictionary and look up the words formed, instead of the player having to type them in, and then there should be buttons for "make this move" and "make a different move instead".
We have been on the fence about this (and still are!). One option is to add this kind of UI in a "tutor" mode that starts on, and can be opt-out at some point. Not sold on it yet, but mulling it over.