John well said and I truly respect your thoughts on the subject,.....as for myself, "piano alone" after a while gets a bit boring as it always sounds pretty much the same, guess I like more versatility in my music in many different ways & genres which in turn keeps it interesting to me if I play alone or with others. Playing piano correctly can be a beautiful thing when both hands are trained to do it right otherwise a weak left hand can make it sound a bit sour and underprivileged to the ear in many ways harmonically and melodically...
I wish you luck in this phase of your journey...enjoy and keep us posted.