Thanks for your response Keet,

As i mentioned in the start post i have export the svg to png

It is created in Inkscape and exported as png 1634 x 4191px

The exported image gives the problems.

What thickness of the lines can you advice?

What is the best way to create good images for the floorplan and floorplanicon? I could not find good information on this.

Here i am more thinking about what size should the images be for the Icon and PlanIcon. how many dpi should i use. What are the best lines to use, think of style, thickness and maybe even color to get a better view. For the moment i keep the PlanIcons in "black/white". but some dark green or dark blue can give an better result on screen/print, that why i ask.
Are there some common traps? like putting to many details in the PlanIcon, at print time it is unclear what is is.

All support is appreciated.