I show specs for a 7.85-8.0K pickup wound at 9,500-10,000 turns.
To combat flaring, if you can mount the pickup with a screw & nut setup, with a stiffening bar on top, that really helps.
Before winding, I straighten the flatwork and run thin super glue around the magnets, top and bottom on the inside, after the glue dries, tape or dip the bobbins.
After wax potting, I wrap the magnet wire area, with black clothe humbucker tape.
Or if you prefer, use the cotten string.
** As to the questions, unfortunately, most will have to be answered by trial and error.
I like DK's bigger wire idea!