While I appreciate the ability to change nozzle speeds for support, perimeter, and top/bottom layers, I find myself constantly having to re-tune the nozzle speed for different layer heights and different infill extrusion widths. The reason for this is that both of my printers are limited in the filament extrusion rate, not in nozzle speed. They simply cannot melt filament very fast and little changes like increasing the layer height can push it over the edge very easily.
I would much rather set a hard limit in Simplify for the feed rate in cubic mm per second, and have the nozzle speed adjust accordingly. This means that the nozzle will slow down for thick infill extrusion widths, but still run quickly for perimeter layers, support structure, and solid infill. This would also help me get the fastest prints possible for a known extrusion limit.
This is particularly a problem on the Ultimaker 2 which is well known for underextruding and the feeder motor skipping even with it's own slicer and defaults. Even on my massive 3DP Unlimited X1000 which has geared steppers and a remarkable feed rate, I still encounter rushed jobs where I need to get a massive part printed where quality doesn't matter and I just need to push it as close to the extruder limit as possible.
Thank you!