I think that those features will make the Yii framework even better.
- Modular application structure.
Being able to make controller/action application is nice, But most of the websites have several sections in them, Those called modules. So if we could make a default structure like module/controller/action i think it will make the framework even more robust and useful.
- Altering the default controller, view, layout directories.
I might be wrong or missed it but currently you are forced to use a certain file structure. like the controllers need to be inside the application/controllers directory the views inside the application/views directory and so on. Something you need to define a different controller directory for your application so maybe i want the controller to be in application/data/modules/controllers ? or the views inside application/data/controllers/views. I didn't find anything about that so i am not sure if it exists.
- Default helpers. Most of the application has several things set by default so those we need some default tools to make coding easier and faster. Like if we had some view helpers such as $this->lang('key') will translate the key to the default language currently set in the application or $this->post()/$this->get will retrieve the _GET and _POST parameters within a view script. Those helpers are just examples of the helpers Yii needs in order to make it easier to write down view scripts and lighten up the application by not setting class member to the view through the controllers.
Those are pretty much the things i find important to add especially #1.