Good Light is hard to define as it depends on the effect and end result you want, however good light is generally light which is enough light to prevent you from going to high with ISO numbers, and personally I would say reflected light, meaning it is softer and would create a larger dynamic range from dark to light. If the dynamic range is higher, you can always adjust in post processing to add more “depth” to the final result. The colour of the light or reflected light also matter hugely, as this will result in a more natural accurate end result as well.
One of the many factors defining a personal style is how they use light to create the unique look, which matters as this sets your result apart from everyone doing the same thing.
There is perfection in imperfection. Don’t try copy others so much as far as a end result goes, but work on something you like. Do not follow a bunch or photographers but rather the one or two you like, which will prevent you from always seeing too many styles and idea’s. Subject matter actually matters the most, as we look at the subject more than the fancy photography a lot of the time.