Quoted for ease
Q: "Is there any kind of set rules for what is included and omitted in the Digi line?"
Yeah, panel space and to omit anything that would be convoluted when it doesn’t have that. They should be more ‘focused’ and ‘boiled down’ without losing too much. To make something streamlined you have to remove a few things. It’s like minimalism in art or music - strip away what isn’t neccessary and focus on the core components. The result will be larger than the sum of its parts.