jkalawe

Default Category is a a helpful workflow tool:
<ul>
<li>
Enforce editorial standards for posts
</li>
<li>
A quick reference for content editors that aren’t regular contributors
</li>
<li>
Each user can have their own set of default categories
</li>
<li>
Site-wide categories will be applied if a user has not specified their own default categories
</li>
</ul>
<h4>Multisite</h4>
Default Category is also multisite compatible as it has been designed for a multisite environment.

WordPress Default Category

Auto select categories for new posts based on user or site-wide settings.

shazdeh

The WordPress Database Reset plugin allows you to reset the database back to its default settings without having to delete the site and recreate it.
Useful tool for theme and plugin developers who often have to clean up the mess and start over.

WPMU Database Reset

Clean up a single site in a WP network, by removing all posts, comments, terms and media files. A clean slate for the site.

WordPress Default Category vs WPMU Database Reset