[klippy]

You can just use flag 'x' and define ADMIN_OWNER to (1 << 23) and use it in your plugins.
Also, 'w' is (1 << 22), '{' is (1 << 26), '|' is (1 << 27), '}' is (1 << 28 ) and '~' is (1 << 29).

The last two (30 and 31) go out of printable ASCII character range, so if you find a way to input it into a file you can still use them. However, that's not really user-friendly. You can change flags for commands separately in cmdaccess.ini in your configs folder so you can squish many flags into one for a specific "admin level", you don't have to use flag 'l' for RCON access for example.

@b3none, 'z' is reserved for normal users. If you give 'z' flag to an admin, is_user_admin() call will fail for them. However, is_user_admin() isn't really great in my opinion, always opt into the flag manager (cmdaccess.ini that is) for commands when you are creating new ones (they opt in by default when meeting certain criteria).