The greatest changes in uniform were the universal adoption of the old National Guard uniform and increasing standardization between regiments.

HaT Industrie makes  a set of French infantry that depicts the soldiers of Napoleon's greatest triumphs.  This is the uniform of Marengo, Jena, Ulm, Auerstadt, and Austerlitz.  Many soldiers may still have been wearing this uniform at Eylau and Friedland.

The HaT set will be necesarry for anyone wishing to field a French army of this period.  The men wear the bicorne and are depicted in trousers.  The proportions are a little off, with giant heads on small bodies reminiscent of metal figures.  This certainly makes the faces easier to paint, but the loss of perspective is perhaps too high a price to pay for a little better facial character.  Do not let it put you off, however: they are still attractive when deployed en masse.  The mix of poses are the best I have seen in a plastic set.  16 marching men in two poses, 16 advancing men in two poses, 4 defending / receiving, 4 standing firing, 4 loading, and 4 officers allow the gamer or modeler to field a convincing looking army with a few boxes of figures.  The officer is one of the best poses in this scale.

Haythornthwaite, Philip and Bryan Fosten.  Men at Arms Series 141: Napoleon's Line Infantry.   London; Osprey Publishing, Ltd., 1983.