Very Lightweight

This is a very lightweight plugin so worth it if you do not know how to add those taxonomies via code. You could extract the code (only a few lines) and add them to your functions.php as there is very little to this plugin, but for those without programming knowledge I would stick to the plugin.

The plugin however does not create templates to display those taxonomies (unlike standard posts). You could copy the post taxonomy templates and modify them if you are able. You will then be able to display the cats and tags.