This looks good.
I like your approach for the start gcode. Have you seen my thread where I’m documenting my first attempts with the DE and Prusaslicer?
It’s interesting that you have different e-step values for the two extruders. Mine have been the same!
Do you really need to heat up both extruders initial when both are used?
I’m thinking of the corner case when you only use the second extruder for later levels.
I’m thinking about a solution to heat up the second extruder only when it is really in use. Furthermore, I do not think I’ll ever do two color prints - I want to use the second extruder with break away filament for support connection points.