Couple of points:
If you are in tigne, the best way to get to sauze d’oulx is: col d’iserain then down the valley on the other side to pick up the motorway through the frejus tunnel. Nice drive, shorter but the tunnel is quite expensive (the 5 day return is the same price as a single though if you intend to go back the same way)
Lac blanc is not open all week, even during the summer ( Sat-tues I think). It also gets very busy, I have never seen queues like it and that includes the pds week at les gets. Pretty good though and as said, pretty techy.
Les 2 alpes to Bourg: red down to Venosc and then the xc trail along the river. Also thallas (red) down to the road and along the road to the Venosc junction and pick up the xc route.
Crankworks will mean more people but the only trail that gets used for the event is the new black, Satan. The rest of the action is near the town, around the slopestyle area.