Here's something similar i made this example plugin years ago, when i first started making pocketmine plugin(s).
Script plugin != easy to install. Script plugins are only used for testing. You should always use phar plugins whenever you release something, even if it is just one file.
But the command there is "helper", you didn't modify "help" :/ Use the one I made. It handles it the best way, executing all the hacks on plugin enable, so the server performance is not affected. (The same way EssentialsPE overrides commands)... Find it here: https://github.com/Muqsit/Help