I think that's the big point - it's lazy route design to always use the same ones. We need something massive... I know! MTF on a well-known climb!!!
I mean, seriously, look at the recent history - Galibier & Alpe d'Huez 2011, Tourmalet 2010, Ventoux 2009, Alpe d'Huez 2008... it's just lazy. There are loads of climbs that are new and/or barely used, but every goddamn year the Tourmalet. Is the Tourmalet a great climb? Sure. Do we need to see it every single year? No. When was the last time we even SAW Alpes-Maritîmes in the route? And Mont du Chat has been unused since 1974; Collet d'Allevard as mentioned above; Col du Pierre Carrée, anyone? You could easily put a finish there, or in Flaine after a short descent. It would fit nicely after the Colombier climbed from the Le-Grand-Bornand side, which means you could still find room for plenty of classic climbs like Saisies and Aravis on the way.