Those are good reasons, unquestionable. And as important as all those things are in your life (kids, wife, cancer history, finances, etc.), make sure that the most important thing about your reason for quitting is about you. Do this for you first and foremost and all of the other things will fall in line. When it comes to the quit itself, it's all about you. Everybody and everything that surrounds that quit will reap its benefits. I'm with you brother. Let's do this.