Let us speculate on the subject of fantasy units...

[Freedom Onanist]

Hey, Kutusov is a special case. Alcahol fueled his creative proccesses!
But yeah, Russia was most famous for its artillery. Russian gunners were widely regarded as the best out there, and Russian artillery was some of the best in the world until the Austrians suprassed them some time in the 1830/40's. Their gunners were famous for almost never abandoning a gun for the enemy, and fighting to the death to defend their pieces.
In fact, the artillery was regarded, in Russia, as the 'aristocratic' branch of the army. Young nobles went into the artillery, unlike the rest of Europe where they became cavalry officers. Too bad THAT ended up biting the Russians in the butt when they tried to update their artillery and none of the dandy officers wanted to learn how to work the newfangled guns.

From what I've seen, their cavalry was regarded as fairly average, although it DID defeat the French cavalry on several occasions.

Their infantry is generally the subject of a lot of speculation. Napoleon, as I said, seems to have been a bit of a Russophile. He's been quoted as saying that if the Russians could give their infantry the 'electric enthusiasm' of the French soldiers then they wouldnt have had any problem taking over Europe. But the problem was that Russian infantry were basically battlefield robots. They cold stand in a line and take fire like nobody and were adequate musketeers (although the Russians didnt bother training their men to AIM, which cost them once rifles became common). They excelled at close-in fighting, and their Grenadiers were probably some of the most feared in Europe, right up there with the Old Guard.

But their offers were widely regarded as the worst in Europe, unless you count the Ottomans as European. They were drunks, and tended to follow the same line as their men in their total lack of flexibility.
Of course, their good officers tended to be VERY good, possibly to make up for all the bad ones.

Regardless of how good they were, Russia probably DID have the most expensive army in Europe. They favored parade ground pomp over actual military skill prior to Napoleons invasion, and paid for it initially. Then, as per usual, they figured out what was going on and kicked ass all the way to Berli-...I mean Paris.

Look at me, I'm rambling! Ramble ramble ramble!

Yes, or you could just have the real Russian winners:

Distance - Captain Middle of Nowhere

And of course

Weather - General Rainy Snow

You could also recruit Major Crap Infrastructure. That way invaders who have invested in their own countries will be completely flumoxed by how to operate in a country where nothing works.

Let's not forget, Sergeant I couldn't care a less about my men