fretless with Luminlay fret lines (that will be pretty cool);
no zero fret (of course not) but ebony nut instead;
and the biggest change is going to the Nordstrand FD3 pickups (just like in my 6 string fretless), mounted at a 10 degree angle, paired with the Glockenklang 3-band pre.
At the moment I'm looking at the option to "invert" the neck, i.e. start with a central wenge wedge but that might not happen.
Stay tuned for the occasional update as we go through this build.