Hello Jeroen,.. imho.. the autotrace is just ok.. and for it to work well,.. it should be a B/W image and high resolution...
My personal alternative,.. is a online converter.. PNG Converter / Convert to PNG (Online & Free) — Convertio
so,.. what I do is get a high res BW image in PNG format... and it converts it to DXF..
Open the DXF into a *sldprt and select the arc/line chain.. and convert it into a Spline (per a resolution which fits the lowest radius).
convertio png-dxf.zip 1.4 MB
Thanks Paul! B/w didn't make it perfect, unfortunately, but defintely better. That online tool works like a charm, exceeded my expectations!