In reply to blanchie14c:
A few observations, based on around 20 seasons in Chamonix over the last 35 years.
Have never been tempted by the Cosmiques Arete. Looks overcrowded, short, one move, not the most aesthetic summit. A poser's climb. Once considered doing it on the way back from the Tacul as a different way of getting to the teleriphique, but there were queues then, so didn't bother. Wouldn't pay 42 Euros to climb it.
I'd go for a lower level summit, with a walk in first to acclimatise, and get a good idea of the geography. The Moine is good for the former, and the Rouges for the latter. Also some wonderful climbs in the Aiguilles, l'M, Charmoz, Grepon, Peigne, Pelerins, where you can be up and down in the day.
Also look at the Argentiere, Chardonnet, Tour Noire. (Aig Tour suffers from overcrowding)
I used to take bivvy gear to bivvy outside huts, but prefer now to stay in huts, it may be noisier, but it is warmer. I can sleep better in huts than on a bivvy. Used to take cooking gear and food to huts, but paper Euros are much cheaper.
There are no cheap bars. Or food. Eat from the supermarket.