While in
Chamonix you can take the Aiguille du Mont-Blanc cable car and exit at the first station (Plan de l'Aiguille) and hike across to the Montenvers Hotel and Mer de Glace. You'll be just below the famous Aiguilles (needles) de Chamonix. This usually takes an afternoon to complete.
On the other side of Chamonix, you can take the Brévent cable car and then hike to the Lac Blanc and then further down the valley. On this side you'll be further away from the Aiguilles and Mont-Blanc. Scenery is great especially at sunset.
I guess your best option while in Chamonix is to visit the Alpine Guide office. They will give you all the info you need. Near the train station you can find the Pierre Tairraz camera store. He was a famous photographer and you can see a bit of his work there.
In
Sion, Switzerland, the main thing to visit is the old town and the 2 castles. You can get some info
here. There's a small (international ) airport in Sion and you can arrange for a flight above the Alps for aerial photography or to please your eyes. Info
here.
If you travel by car, the scenery from Martigny to Chamonix is fantastic. Just before driving down in the Chamonix valley, there's a pass called Aiguilles Rouges. This is a beautiful place with a direct but remote vista of the Mont-Blanc and all the Aiguilles.
Nnmmaa provided excellent suggestions for
Zermatt. When you're there, ask for the Hörnli Hut. It's a very large mountain hut located at the foot of Matterhorn. Last year I planned to hike up there but an injury in my back made me stay "home". I'm not sure how long it takes and consulting the local mountain guides will provide you with the info.
You can see a photo of this hut
here.
I've never been in
Lugano, sorry!
Good hiking & shooting,
Francois