Personally, I've found one of the more stimulating ways of playing in recent times has been to kind of move outside the free improvised area and work with people who are probably improvisers but they have a particular way of working.
But now, being a parent, I go home and see my son and I forget about any mistake I ever made or the reason I'm upset. I get home and my son is smiling or he comes running to me. It has just made me grow as an individual and grow as a man.