Of course, all component Joomla native facilities are working.
Templating each different templates files of each different views is possible in your main website template files.
For css, it depends how you implement them in your template, the right use is to load is :
$doc = JFactory::getDocument();
$doc->addStyleSheet('myCSSUrlFile.css');
see how in helpers/helper.php
function headerDeclarations()
{
//CLEANED TO MAKE IT EASIER ... (not your original function)
$doc = JFactory::getDocument();
//Javascript
$doc->addScript(MY_SCRIPT_URL);
//CSS
$doc->addStyleSheet('MY_CSS_URL');
...
}
This is how your component files are loaded in the header.
You should do the same in your template.
If it not working, I should have a look, but it depends the order Joomla does.
The component is loaded before the template, so it should works !!