Linear deflection limits the distance between a curve and its tessellation, whereas angular deflection limits the angle between subsequent segments in a polyline.
If you know the new values are way too high you already have a starting point.
The current values give you millions of triangles, linear deflection can be cranked down quite a bit.
For images that are less filled with arcs and circles the angular deflection can be played with.
All comes down to how fine the original SVG file is and at what size it is supposed to be printed.
I honestly never bothered with the SVG import in Studio as I do this step right in my CAD program.
There I can see when for example text or fine details start to turn rough once the deflection values go too off.
A workaround to not loose too much detail and to not have to adjust levels all the time based on the SVG demands >
If it is possible to just import the SVG file it should be no problem to reduce the creation through the mesh options.
Really makes no big difference if you simplify the SVG upon import or once created.
But as said, I am not really using Studio for this and if I have to create a SVG from an image or such I am lucky enough to still have Vector Magic working on an old laptop.