What would all these commanders do? It's like...too much of them. A maximum of two generals with their adjutants and some cavalry for protection (15~20 men) should be enough. These two command formations would provide aditional morale to nearby troops (they could also influence accuracy of shots).

Also priests should be replaced with a medical unit which could be trained at the academy. This unit could consist of a medical wagon pulled by 4 horses and 2 surgeons/medics. Just like the priests this unit would heal formations in its range (and possibly also provide aditional morale).

Sappers should be able to construct boats big enough for one infantry company or two cavalry squadrons. Sappers should also be capable of constructing earthworks for artillery positions like they exist in the editor. But the player should be made capable of directing the length and direction of the earthworks. With enough material, a player could theoreticaly construct a sort of limes. These earthworks should be made destructable either by artillery or grenades.

Some other stuff should be improved aswell. Namely, the British should have the option to create pipers for their highlander units. All cavalry should have an officer and a trumpeteer added, not just a flag bearer (again for improved morale).

Another formation type should be introduced. The L shaped formation. It would provide better defense on the flanks. Half of the infantry formation would simply move to a 90° angle. This could also mean that two companies instead of four could create a square.

Hmm, this is something where I do not agree.
I never hear about specific L formation. Normally such thing can existed in special circumstanses, but it can not helped too much against flank attacks.
Square formation is and should be create as battalion square. But it could be little bit bigger in size as like it is in C1, AC or HEW.
In the game aslo could be multibatalion squares, but this can be achieved even now when you form 4 battalions in line and ordered them to form something like big square.

I'm not saying that such a formation actually existed during Napoleonic Wars. It could be just an aditional type of formation. And I disagree with you on its use on the battlefield. The L shaped formation can change direction quicker than a line formation. This is especially important during an enemy cavalry attack as half of the company is already facing the enemy.

IMHO 2 two-company squares can move into battalion line formation easier and with less danger from a possible cavalry attack than 1 four-company square. At least in the game. I'm not talking about real historical battles (you must agree that some real-life historical stuff must be sacrificed for better and more enjoyable playability).

L shaped formation can not withstand enemy flank attack because it had lower fire power, still was poor manoueverable and it could be surrended.

If in nearest place was another cavalry which could counterattackd then enemy cavalry did not attack on infantry. In such case cavalry waited on support and then their primary goal could be enemy cavalry. Look at Battle of Valutina Gora 1812. Murat's reserve cavalry waited there, because they saw few Russian cavalry units placed on Russian left flank. Junot's Westphalian Corps did not came with needed support and Russian can withdrew.

It is interesting, but I still disagree on L formations. It looks little bit strange and was not normal regulation at that era.

Sorry I would like to see in the game more realistic things e.g. cavalry squadrons and regiments, artillery sections and batteries.

Check the picture again. The same goes for line formation. Besides, in L shaped formation, the formation ends are closer than in line formation because of the 90° angle. So a firing order for the whole company would mean that all soliders in the company would be able to fire their weapons (at least in the red zone when the enemy cavalry has already smashed in your formation, possibly even in the yellow zone). Whereas in the line formation, one end of the company can not support the other end because it is too far away.

No progress is regress. Perhaps a change of tactics would give Napoleon victory in Russia? Who knows? YES, the L formation is probably not historicaly accurate. But let us not forget that this is just a game. Some things DO need to be sacrificed. The L shaped formation could represent individual commander's initiative on the field of battle.

So...On one hand you'd like to see macro management of your army (squadrons, regiments, divisions, armies), and on the other hand you want micro management of artillery sections and batteries?

Above all, games should be fun. That's why they are called games. 100% historical accuracy in formations, tactics, strategies uniforms,...is for military academies.

I wrote about possible situations on battlefileds. In the game L formation can looks even worse when soldiers can fired above their felows heads.
It is crazy enough when all soldiers in column formation can fired at once. Now you propose implement such case also in strange L formation.
It is clearly looks unrealistic.
No, no it can not be good idea.

This is all historical realism here or is it not?

Horses should also be manipulated in such a way that they don't automaticaly get killed together with the horseman. Instead surviving horses and also horsemen whose horses got killed but they themselves survived shoud rally back at your stables.

I havent added any but I remember someone saying they have to be symmetrical.