> Design makes all the difference and creates real business (and user experience) value

Yes, design adds value, but the graphical aspect (margins, branding, etc) adds less than you think. In my view, given two technically equal systems, design only decides which system users will gravitate towards. Without good design, users will happily use your system, unless they know that there is a better-looking version of the same system elsewhere.

So this makes graphical design mandatory, but in a way that is to a great extent decoupled from value.