Well a "hobbyist" classification might be interesting in that it can be an indication of how competent they are and likely to know what they are doing or not. And how likely they are to respond to issues if contacted. Hmmm. This leads me to think a simple classification is not the answer, but a classification based on a short list of qualities such as:

connectivity type, network scale, technical skill, and responsiveness

Of course being about to determine the last two elements might be subjective and only possible when actual issues arise to report.