Shopify allows us to add tags to our products with there being really no limit on how many you can add.  These tags are great for creating collections and so on. However, the tags become overwhelming in the filters when you have products that span several collections and relevant other products.  Tags would work better and also be better organized if we could group our tags within the filters or have the tags become their own filter box. 

Here is a scenario to use to get an idea.  One of our smaller collections is batteries.  For each product in this collection we have a tag for:

• Voltage (1.5V, 3V 7.2V,7.4V, 8.4V, etc)
• Battery Type (Li-Po, Ni-MH, Ni-Cd, Alkaline, Li-Ion, etc)
  
• Connector (Deans, Tamiya, None, Mini, XT90, Banana)