That's what I would prefer too, but I don't think this is going to happen any time soon 🙂
I know this approach is more expensive, but it does at least work - no matter which firmware is installed,
I can easily wait for some seconds/minutes if the print doesn't fail then.
Btw, the difference is not THAT big (around 0,2 seconds on my current 120 layer print).
I suggest to add a dropdown field named "z Offset method" or something like that, where you can decide which ob both methods you want to use, something like:
1) `classic G92 (fast but not supported by some UM firmwares)`
2) `global offset adding (slow but robust)`
You could then preselect one of both types depending on the gcode flavour.