I would love it if shortcodes could be added into the Template files. It'd be much easier for me to write [list_categories orderby="id" showcount="3"] than <?php wp_list_categories('orderby=id&showecount=3').
Even better would be
The reason is that all those starting and ending php codes <?php ?>. It makes it harder for me to read my code. A good system of template tag shortcodes would make coding and managing our code much easier.