My first playthrough was 2 lonewolves because I wanted to see how powerful one could get (that lonewolf talent was teasing me throughout my first attempt at playing the game)
After achieving practical invincibility I encountered a problem - out of hotbars for my gazillion skills! So now I'm playing with 4 and specialising them appropriately. As for the companions they do add more to the game I found and can't really see myself doing another lonewolf playthrough.
Unless I want to be a demigod again