While I hum and ha over a War of 1812 army, my butterfly mind has alighted on the new plastic Prussians, simple easy to make figures that even I may be able to finish.
A quick look at Waterloo orbats shows a corps with 4 brigades of 2 line and 1 Landwehr regiment with some attached skirmishers, sounds good so far. Guns and command are already out. That just leaves cavalry.
In the interim I have looked hard at the Perrys French hussars, if what I read is true then figures would wear hussar dress with overalls and a covered shako. The horse furniture changed in 1815 but I doubt that it was widely issued by Waterloo. That would just leave some medium/heavy cavalry and some Reserve plastics to form a decent corps.
Thoughts?