It would be nice if we could add an aftermarket custom build plate and since certain plates have different thicknesses, to be able to basically name the plate and have box to add the z-offset and be able to save it without needing to go mess with the gcode.
Just adding a custom plate would be good enough since there are so many aftermarket plates
There is seldom a reason to adjust z-offset for a Bambu printer.
Changing the plate thickness does not require a change in z-offset. Bambu printers adjust automatically, using the nozzle to determine the position of the top surface of the plate, making that z=0, regardless of how thick the plate is under that surface.
Because a textured plate has peaks and valleys spaced more closely than the width of the nozzle tip, the nozzle only touches the peaks, and cannot determine an average height. There is already an automatic adjustment for this plate in the Machine Start G-code:
;===== for Textured PEI Plate , lower the nozzle as the nozzle was touching topmost of the texture when homing ==
;curr_bed_type={curr_bed_type}
{if curr_bed_type=="Textured PEI Plate"}
G29.1 Z{-0.04} ; for Textured PEI Plate
{endif}
If your aftermarket plate has a more heavily textured surface, requiring a different amount of squish, this well-commented section of the starting g-code is very easy to locate and change for a custom printer profile.