Thanks very much. As you can see, my history there has been very sporadic; I wish I'd had at least a couple of years there like you. Last year I was in Paris from May to November, and returned to Montmartre a few times. I explored Paris more widely, but often hung out at the Trois Mailletz, a great bar, with a kind of Montmartre atmosphere, which has a very good pianist and very good opera/chanson singers. It's in Rue Galande, just across the river from Notre Dame on the Left bank. It gets tourists but also locals, some are real characters -  highly recommended. See

Trois Mailletz/Caveau Huchette

Flaneur

Maybe it's because I'm a Londoner - that I moved to Nice.