As a baal tfilaoh, I love to use R’ Shlomo’s nigunim. They are indeed on a spiritual level of their own.
I also recognize that he was a man who loved his fellow Jew perhaps more deeply and more sincerely than almost anyone in his generation, and in that he was an example for us all.
As to his general “touchy feely” approach to men and women, it seems on the face of it poshut that it wasn’t done in a halachic manner, but he had his own justifications, acceptable or not.
However.
The testimony and evidence of his behavior, especially with young women, especially when they were vulnerable, seems straightforward and overwhelming and is available for anyone to research. I am sure there are many, many people out there who did more and worse and with violence to vulnerable people; but that doesn’t excuse his behavior, especially as a musmach and a putative role model.
It is a real challenge for us, determining the line between a character flaw and a dangerous compulsion.