In reply to John2: I'm up in Cham and have yet to ski Contamines - keep meaning to though!
I've heard it's as described - fairly French, fairly chilled out and good skiing.
I think your days in Chamonix will be limited though - we only get 3 days in the Haute Savoie on the Chamonix pass.
La Grave? Might be a bit small but I've heard it's a friendly scene...