As usual problem that different people want/need different keys and sets snowball with price skyrocketing.
Maybe the best way to do this adapters is more like how EK sell GMK keys, in pairs?
Maybe have a 2x style full touch caps locks like "Caps Lock' and lock icon example
ANSI enter and 1.5 \| pair
shift set, text and without text
1.25 ctrl pair, 1.25 alt pair, 1.25 Windows/menu set
1.5 ctrl and alt pairs, 1u Windows/menu set