Hors catégorie

I'd pick where you are going to stay first, then work from there.

If it was me I'd do the Croix de Fer, because it's hard, beautiful and close to the Galibier and Madeleine. Something like the Saises and Cormet de Roseland would be good too, and on a clear day you get spectacular views of Mont Blanc.

Spot on, the Croix de Fer is a wonderful and tough climb. Also the town of Allemont is at the southern foot of it and may be a good place to stay. A lot cheaper than Bourg too. You could use it as a basis to do a marmotte type route.

You ought to do Alpe D'Huez if you're in the area, just to say you've done it.