Hi Myke,
to answer your question, i ’d like to refer to our discussion one year ago 
:
@nefelim4ag this should also answer, why manta’s SPI is not in use for the ADXL - it is reserved for ADS1220 (whenever i have managed to build a working load cell endstop).
Somewhere in that Topic i may also have explained why i do not use toolhead controller boards, but in short:
I like to avoid having the stepper driver for the feeder within the build chamber, since i reach temperatures around 70°C in there. That doesn’t seem to be a good environment for stepper drivers.
On the other hand i kept my toolhead extremely slender and lightweight.
X-stop Z-stop, ADXL, fans and feeder are the only components i accommodated there in a very compact manner. There is no room for an additional MCU there - and as far as i can see, no need also.
