Be nice to have a setting for this next to Icon Size. Mine on this field are too small to even use.
Can you post a screenshot? The size of the spheres changes with the size of the bounding box. If I make the box very small, they get respectively smaller, but when I zoom in, they are just the right size compared to the overall size. I have full control over this stuff, but need to see what you are doing to understand the problem…
Looked at the code.
You can open the file StokeField_GridManipulator.ms and change the line
if size < 0.1 do size = 0.1
to whatever size you want, e.g. 1.0, 5.0 or whatever.
This way, the sphere handles will never get smaller than that value.
I will see if I can expose the Min. value somewhere…