Mercedes Benz is making the same mistake that Ford , GM and Chrysler did decades ago which is to have too many configurable options in their model line up (which is currently about 30 different bodies). More tooling , more products, more inventory, more safety stock. They built their brand when they had 5 models in lineup and change over happened every 10 years.
It's impossible to have this much variaty and be efficient or effective at the same time.