Exactly!
In 2010 I developed a full modular analog DJ mixer system. A 4 or 6 channel version where every single function (EQ (3 way, 4 way, parametric), dynamics, aux sends, effects, input stages, long/short/rotary faders, balance knobs, meter…) could be arranged by the customer. Just buy the modules you like to have. From a simplified rotary mixer with only volume knobs per channel to a huge system with everything you can imagine in a per channel basis. Allways extendible and alterable, open for many function more to invent. All connected via special DSub connectors (or maybe later in a case with a fixed bus connector inside…).
Since 2010 the prototype device lies in my basement. Sounding great but stays untouched ever since. Just because oft the reasons you mentioned.
Now I have a kid and a wife that is not able to bring much money into the family. I need a stable job and I have to renovate the old house we’re living in. Have no workshop ATM. Times change. I can totally understand that this fantastic project is paused.