This tool doesn't display models contained in a CASC or MPQ storage, it loads the texture from them to correctly render models that require texture from the game.
When you download a model from hiveworkshop, it usually has a readme.html that compiles the information from the resource post. You can notably find the list of tags in it.
I just added a tagging feature that reads the readme.html and automatically assigns the tag to the model.
In version 1.3.0, you can now filter by tag, add or remove tags.
HD models add more layers of complexity, I am simply not interested in those, therefore I will not invest myself into it.
Maybe someone like
@BlinkBoy might be interested in making a more efficient model explorer.
It should work, but if you open a folder that doesn't have the favorite models, then it won't display even if you filter by favorite.