Thanks for trying it! Do you think undo would be okay if it “cost” you a turn? Part of the fun (for me at least) has been the competitive nature of it (ie, competing on getting the lowest turn count)
Perhaps you can have competitive and casual modes? One with the score and no undo, another without and with respectively.
There could be an official word each day that is ranked, but also randomly generated puzzles that you could play limitlessly. Only issue there is when you have words appearing in the casual mode and ranked mode, which I'm not entirely sure how to fix.