My friend and I labored over the word lists for our word game subletters.fun. We wanted the word pairs and at least one optimal path for each word pair to be from words on one list, which were simpler words that we would expect everyone to be familiar with. But players could use their own more advanced vocabulary to solve the puzzles on their own without feeling restricted. Then we bundled literally 10 years of unique word pairs into the game and shipped it.