It's been a looong time since I was there, but I was there in winter a few times. January I remember as generally dry and cold, good in the sun (unless you go to Cimai where it's only bearable to climb in the winter as it's a boiling sun trap. Good, old school, fingery-technical-powerful. You've probably been Ian?)
Monaco has its exposed faces, and sheltered nooks and crannies to catch the sun. La Haine (France's first E7?)is pretty sheltered, don't recall how much sun it gets.
Provence in the winter sun is nice IIRC.
Paroi des Toits (Luminy, Marseille) would be nice in winter I reckon as it was warm in spring.