Improve readme

README.md

@@ -23,16 +23,18 @@ The UI is structured as follows:
 
 ## First steps
 
-Try Fencer on the font that is preloaded, a custom build of Sofia Sans, a 2-axis font (Weight and Width) with this simple master structure and default at 400,100:
+Try Fencer on the font that is preloaded, a custom build of [Sofia Sans](https://github.com/lettersoup/Sofia-Sans), a 2-axis font (Weight and Width) with this simple master structure and default at 400,100:
 
 |          | wght=100 | wght=400 | wght=900 |
 | ------    | ------   | ------   | -----    |
 | wdth=100  | 100,100 | **400,100**  | 900,100 |
 | wdth=62.5 | 100,62.5 | 400,62.5 | 900,62.5 |
 
+_Note: The current shipping version of Sofia Sans uses a more complex master structure, since – without avar2 – the design space requires additional masters to represent the designer’s intentions. The avar2 mappings allow us to avoid the additional masters, and thus reduce font size and simplify maintenance._
+
 Now let’s say you find the Black ExtraCondensed (900,62.5) instance to be too heavy. We can add avar2 mappings to help.
 
-First, let’s add some instances to help us visualize what is happening, as follows:
+First, let’s add a few instances to help us visualize what is happening, as follows:
 
 * Set the location to 400,62.5.
 * Click the “Add Instance” button.