That's an interesting debate you have there, my two cents on this is that first there's actually only a few honorifics : sama, san, kun / chan (without variations such as tan, dono and the likes which are semantically the same). These only refer to degree of respect and distance but don't give any input on the profesionnal or personnal character of the relationship. Also in that regard the absence of honorifc only imply that you are very close to the person or a lack of respect.