In reply to apd:
As has been said Aiguilles rouges has lots. Some snow patches linger in areas depending on when you go and that season's snowfall. Often access is fine with trainers and on many routes you can leave rucksacks near the base. Lots of bivvy sites within 5 minutes of Index chairlift including the old station which has lovely soft ski cushion mattresses and, being close to the lift, means you can carry luxuries!
Piola guide is great ' The Aiguilles Rouges 1'. From this bivvy site here are a few recommendations:
Aiguillette de la Floria: 6 nice 5/6 pitch routes 5b / 6a. Quick access and descent. 10 minutes from bivvy. Arete Rouge is great. Friendly first multi pitch crag.
Grande Floria: 10 5a - 6b 6/7 pitch routes. 20 minutes from bivvy. Abseil or walking descent or possibility to go up to summit via three more lovely pitches.
Pouce: Awesome big crag. 14 plus pitches. Voie des Dalles and Voie des Francaises are lovely.
Aiguilles Crochues: Many varied routes. Voie Ravanel is about 16 pitches 5c.
There are several more routes within 10 minutes of the bivvy but they are often busy. If bivvying just wait until the crowds have gone in the later afternoon and even the really popular routes can be quickly climbed with nobody else around.
Walking up to an hour in either direction from the bivvy opens up many more routes. Perseverance, Pourrie and many more.
Mid level Aiguille de Midi station has bivvy sites nearby. Sometimes some soft snow may need to be negotiated. On the Peigne slabs Lepidopteres is a lovely little climb and Arete Papillons, a great route, is more alpine in nature. The summit of the Peigne can be reached via great routes and Voie Contamine is an awesome 6a route.
Have fun!