I really like that in regular quizzes, there is a "play pronunciation after answering a question" toggle that saves a click after every question. I'd love to see the same feature in Shiritori Cat - auto play word audio after you or the opponent sends a word.
In addition, I would love to see an auto expand word definition feature, without having to click on every word sent. Though I understand that may be less popular, some words having very long definition and all.