Normally France will have to aid Italy anyhow and can easily defend against your large stacked German army in Belgium. Now on your first turn we do not attack Belgium, making France having to defend multiple territories
By moving a large force to Swiss on your first turn your army is still flexible to go out all directions. If France aids Piedmont and Italy’s army there doesn’t move then you will be facing max 13 infantry, 4 artillery from Tuscany, Piedmont and Burgundy. France will need to reinforce Burgundy and Marseilles at the same turn. The good thing is that there army is spread among many countries. On the other hand you can attack Piedmont with 18-1 (loss in Swiss battle) infantry 6 artillery and one fighter.
Result would be 8.5 German casualties versus 11 Allied casualties
Venice will fall to Austria on the same turn (most part of Vienna army is meant for Italy) leaving Italy wide open.
Basically Italy can only hold the line if they withdraw at their first to Tuscany, but that leaves the France army toasted in Piedmont. If the France do not defend Piedmont a large German army can make a strong attack on Tuscany on turn 3.
Meanwhile it might be a good idea to purchase a battleship with Austria or an additional fighter