importing new templates gives you the opportunity to select what should happen (update this, create these etc.).
But often you can't really understand what will happen if you import a template. Especially big templates are often hard to understand and overview. Thus it would be great to have a kind of a dry run for importing templates which shows you would WILL happen if you import this template.
I think this is also kind of a security issue. Imports my harm your system. So I set the priority to "Medium".