A cartridge's ability to track correctly depends on a number of things, however the range of acceptable VTF is very small. To set the VTF at "what seems like a light force" is madness. There may be legitimate reason to change VTF to suit a particular record, but get a good scale and experiment with the VTF within the range recommended by the manufacturer. Most cartridges cannot track correctly at the low end of this range except on the very best tonearms. Set it too light and the stylus cannot maintain solid contact with the groove. The stylus can then bounce around causing groove damage. It's better to be a little too heavy than a little too light.