This compilation could be interesting. There are some good ideas nevertheless few things are not clear to me.
As I can understand you plan implement some smaller states as playable factions as like Denmark, Portugal, Holland, Bavaria, Wurttemberg, Saxony and Hessen.
I guess this last one it will be Hessen Darmstad not Hessen Kassel which was part of Kingom of Westphalia from 1807 to late 1813.
I wonder why you do not include Polish faction as playable. It could be interesting for many players.
Poland had very impresive history at that period and Polish formed much more units than all these mentioned above states.
They fougth hard in many campaigns e.g. during Russia Campaign in 1812 they formed c.a. 100,000 men under arms.
There also existed Duchy of Warsaw and Republic of Danzig from 1807-1814.
Few years earlier there was big Polish Lithuanian Commonwealth which cased to exist in 1795, but Polish still fought for their independence, therefore they formed many Legionary and other type of units in French servise.
I wrote today short information about few Polish units here http://www.twcenter.net/forums/showthread.php?p=10251330#post10251330
Do not forget about Polish uprisings too. There were many greater and smaller revolts in 1794, 1797, 1806, 1830/31, 1846, 1848 and 1863. It was little bit earlier or later than Napoleonic period, but it shows that Polish still wanted to fought for freedom. It could be interesting event in NTW mods too.