Hi there Joel.
Either Tags or a Custom field would work fine for your purpose here. Although I would say tags would be a more robust option considering you are trying to categorize your contacts by multiple metrics.
This sounds like a great project to scope out with our Professional Services team - If you havent already had your free hour of consulting with us, I would recommend we set that up together.
Please feel free to email us at Success@method.me or jump on our Chat referencing this post and we'll be happy to get that ball rolling.