Here's another vote for WW2 Italians, and field artillery in particular.

Apart from metal, there are field guns (of French and Austro-Hungarian origin) available in styrene but the 75mm Cannone da 75/27 mod.06 is lacking. It could be used for WW1, WW2, the SCW, and in many armies since their Krupp guns are very similar.

Yes some Askari would be very welcome too. They were indeed very faithful troops which fought in many cases until the last bullet

Some troops of WW2 are missing...gurkas, moroccan mountain troops (goumiers), libian inf.for the Italian army.

I was just about to say that - second vote for Libyans!

Another vote for Italians, the Waterloo 1815 sets have such a mix of figures that it is very difficult to create ordinary Italian troops.