In no particular order: consistency, honesty, their time, moral/professional ethics and professional skills/knowledge to meet each client’s needs.

The differences you mention stem from which school of thought and/or personal belief these Ts subscribe to. As such, there will inevitably be much variability: e.g. amongst those who hug and don’t, those who validate or challenge etc. This is where clients can choose - upon interviewing many different types of professionals, which one (i.e. therapy modality and person) they best click with.