Here I will show things for the printer itself what I have designed and printed.
I think these things are very helpfull.....
Fan for the extruder gear (blows air through a channel to the extruder gear. Connected in parallel to the upper fan) - reduces the softening of the filament at high room temps and extruder temps
And here is the stl for the toolholder/filament waste bin. You should print the holder and the box upside down (and the cap with the bigger surface down). You can print the box and the cap the same time.