An often ignored design ... at least outside of rockabilly ... is the DeArmond Dynasonic ... or 2000. Top end clarity and bite, bottom end slap and grind, yet not as 'middle heavy' as a P90.
Here is my first prototype bobbin and plastic top insert (white here ... but production ones may well have a choice of black, parchment, mint or 'tortoise shell'.)
I will be dispensing with the mechanism, and pre-setting any stagger to the poles (fine with modern strings), though keeping the distinctive adjustment screws as simply dummies. I will also be making these with the standard humbucker and soap-bar P90 form factors to enable the widest spread of users to be able to fit them to their guitars.
Bit more jig and tool making to do yet ... but all part of the game