I'm curious if there is a way to change the official CLI or GUI wallet password.
CLI: The new version (v0.11.0.0 at the time of writing) has an option to change your password. Simply type
password and it'll provide you with an option to change your password. As a general remark, you can type
help to obtain a list of commands and their options.
GUI: Currently aforementioned option isn't implemented (yet). You'd have to create a new wallet by restoring from the 25 word mnemonic seed, which allows you to set a new, different password as well.