Refining tags

This discussion is about adding tags to better refine choices for those tags that give too many results or are too broad.  
An example could be changeling. There could be tags for color or subspecies of changilings. Like, blue, orange, or green changeling. Spider, scorpion, or bee changeling.

I’ve started to do this sporadically with the Pokémon tag

I would love this. I think there should be more of an awareness so others will be adding tags to make searches easier. I would personally love for there to be more when it comes to OC. Like earth pony, unicorn, and Pegasus.

@RagingBlackTiger  
But all those tags exist.