That's a nice print, in fact you just gave me an idea to make something similar for lab test tubes. Those stainless steel holders for test tubes are kinda expensive here so why not print them

I suppose thicker wall is the same as perimeter settings is Slic3r so you might have some luck with thinner parts if you increase it.

Anyways almost every part is unique and unfortunately there is no universal setting that works well on every part. But hey that's why 3D printing will never make you bored