Saddle Library

I've just been trying to come up with a quick descriptive framework for different types of saddles so that people who aren't very bike-savvy can try a saddle, then say "I think I need something wider/firmer/etc"
My first stab at it here has 3 categories with 4 choices, but what am I missing?:

1. width narrow medium wide extra wide
   
2. middle flat dip cutout large cutout
   
3. surface hard firm soft extra soft
   
   

so it looks like this with a few examples of saddles people may be familiar with:

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