You can add AirPods charge widgets on your iPhone, iPad and Apple Watch. On Mac, there is no built-in option to add a charge widget. However, you can check the charge of AirPods and case through Menu Bar or System Preferences.
Enabling the "Filter Unknown Senders" option allows you to get rid of message notifications from unknown senders on your iPhone. You can also view them periodically in a hidden folder.
You can change notifications sound on your iPhone for default apps and actions. And you can also use iPhone settings to change sound for a specific app notifications, but that works not for every third-party app.