Modules

Replace 'third_party' to 'Modules' for HMVC applications!
I suggest to load module using the following code :

Code:

$this->load->module('path_inside_modules', 'rename_if_need');

then use it as codeigniter "application" like :

Code:

// path: "/www/ci/application/modules/path_inside_modules/views/welcome.php"
   $this->rename_if_need->load->view('welcome');
   // if above is impossible!
   $rename_if_need->load->view('welcome');

Just like loading library.
Module loader might need controller loader also, to execute functions in that module controller.
Ci4/Router and any related components should support modular applications by default!