A glaring omission on the M200 is a menu option to check the head temperature.
When replacing heater cartridges etc, it would be nice to have the option to set a temperature then read directly from the sensor to see if the ACTUAL heat value was within expected range.
A temperature calibration facility would also be nice. ANOTHER REASON why you should open source things.
The M200 is a PITA for hotend problems which is why I have just made my own (slightly larger) heating block out of brass, and bought a micro swiss all metal hotend.
The other thing I have done is machines small fins into the block, this allows the temperature to rise and fall more quickly with the fan operating, but keeps a good thermal dynamic overall.