Variable layer height is great. Especially combined with “combine infill”. It’ll take a little longer, but I tend to compare print time + post-processing time to the print time using variable layer height.
You can also adjust the height range in the machine settings in Studio. For PLA, 0.04mm is pretty easy with a .4mm nozzle or larger. 0.03 is doable, but out-of synch with the stepper motor pitch. “Multi-color interlayer” uses a speed trick (to 350mm/s) to push all the way down to 0.02mm layer height.
Even with the increased print time, it can be much shorter and, more importantly: hassle-free, than a fast, coarse print with long post-processing.
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PS: Just in case you have trouble finding the slicers machine settings: