Overall I normally recommend Danzo - although I don't think the field will actually * that often with how far back his placement is. If you're set in stone on having him in the last slot like that you would get more out of using sasuke, at least then you could override one of the automatic field changers.

You can run any main with whatever team you want. Doesn't mean it will work well. Fire main is in a weird place right now since his skills were... shifted. He's still viable, but you can't just pick up a lightning main team, slap the fire main onto it and call it a day. You c*e fire main. You c*e that team. I would not recommend using fire main with that team though.