Couldn't agree more with your rue Marlar and St. Dominique recommendations.
When in Paris, over the last 25 years or so, I usually stay with a friend on r. Jean Nicot and so know the neighborhood well. Both l'Ami Jean and l'Affriole are great. And two years ago I dined at Cafe Constant. As an aside, I met M. Constant about ten years ago at a New Year's eve party he was hosting in his r. Jean Nicot apartment, since he is a neighbor of my friend. The cigars and champagne were everywhere, but the view of tout Paris from his penthouse was awesome!