We love Annecy but mostly as a change from skiing villages. Worth adding to a list of suggestions though.
If you like Chamonix, how about nipping through the tunnel to Courmayeur in Italy. Some lovely bars and restaurants in the town centre. Early evening the locals put on a promenade too.
edit: I would avoid Flaine unless you're skiing. We've skied a couple of day trips in Megeve but never stayed there - worth looking at though.
edit again: how about St Gervais?