Design can and should be an fundamental part of instrument making even though few makers consider it a relationship worth nurturing. Since this is a home for owners of the most spectacularly beautiful and functional instrument designed, perhaps there are people for whom design is (almost) as dear to their lives as music. Maybe a salt shaker isn't so trivial--you must commit an entire day searching for an artful salt shaker before you part with your money; maybe Moog's instruments, as fine as they sound, have always bothered you, appearing as if designed by a high school wood-shop teacher; or maybe your turntable needs to sound good, look good and work well.
Teenage Engineering is the best embodiment of good design amongst instrument makers for me, but there's a minority of makers who also make things and make with care.
If there's any interest, perhaps this could be a place where we post music-related creations (instruments, home audio, etc) created lovingly, holistically--design isn't an afterthought, it's elemental to it all.
Here's a few to start.
Ableton Push 2
Future Audio Workshop's Circle². A different aesthetic approach to UI design than the OP-1, but appears just as intuitive, instructive, engaging and immediate. Also uses a new type of synthesis.
People People's Transparent Speaker. Also the worst hiding place for Hide & Seek.
Koma Elektroniks. Effects. There are infrared sensors for modulation.
Bowoo. Case for our buddy.
Modor NF-1. Digital synth with knob-per-function interface. Also, it rhymes with Hodor.
Some nice sounds demoed here: