css in default template

links to style sheets should be inserted to and not to as we can see in many .tpl files in default template...

not really!

If there are mulitple style sheets for differn't content.

If people start adding there own work iI don't want people to have to alter the main stylesheet or layout.tpl.

It would be good to get the markup as semantically correct as it can be - and contextual selectors can take care of changing content.

Opencart's separate stylesheets make it very easy to edit templates, but it would be worth sacrificing that convenience for a more properly presented page by condensing them into a single file - that or figuring out a way to update the header used for a given section if the css file becomes too large.

A quick kludge could be 2 or 3 css files and then copying the logic from further down 'layout.tpl' to select the right one to include - but like Daniel says, that would mean people having to delve deeper into css and templates than some might normally need to.

As css is such a major part of how websites are built, it might be worth adding in the ability (e.g. a mini template file or something more elegant that still avoids using the database or making directory calls) to let users provide a stylesheet or javascript for a given 'section' of the site within it having to be in the body of the document.