You asked about preferred order of tasks in neck building. This is the way I've done things over the last couple of builds and currently my preferred order but it has changed almost every build to this point and will probably continue to change with future builds:
- Square off neck black
- Pencil mark everything from truss to headstock angle, where heel starts, etc
- Route truss rod channel
- Cut headstock angle (front) then plane it flat and square - I like 11º
- Rough cut neck underside profile, headstock angle, volute, heel. I do all the above on the band saw then leave it for a day or two in case it wants to move
- Glue on headstock veneer then plane it's top edge flat with the top of the neck (creates a flat for the nut to sit on)
- Rough cut the neck taper and headstock shape then leave it a day or two before routing final taper
- Thickness fretboard blank to 6mm and glue it on after installing truss rod (I use 6mm Graphtech nuts)
- Trim fretboard edge then route it flush with the neck taper
- Drill access through headstock
- Radius the fretboard
- Thickness the back of the headstock (spindle sander)
- Mark fretslots with centre line and protractor
- Cut fret slots
- Put off inlay work for 2 months
- Inlay fret board and do all the sanding
- Hammer frets in
- Carve the neck
- Levelling, crowning etc.
I always aim to build the neck first in it's entirety, but I nearly always get excited and start carving body half way through neck build. But If you're impatient like me, it's a good idea to be working on the body when giving the neck time move after rough cutting.