-As far as I understand it it was not only winter that caused the degeneration of the Grande Army but the choice of retreating along the same Smolensk road that they used to advance for fear of risking a confrontation with the Russian army deep in the territory.
-The Russian army did not retreat from Borodino after suffering 'some' casualties, they lost 40,000 out 120,000 men and the choice was made to save the army instead of it being destroyed in battle.
-The multi-national make up of the Grande Army was not a mistake. Non French troops like the Italians fought effectively and other armies such as the Anglo-Dutch managed to hold Napoleon at Waterloo despite dubious Dutch quality. Furthermore its rather obvious that not using these troops would have resulted in more French units being used to garrison the positions making the core army even weaker.
-Berezina was a French disaster, not as big a disaster as it could have been but a disaster non the less. Just because a French force manged to survive does not make it a French victory, using that logic I can claim that the rear guard actions of the Russian army were victories too, ones gained with significantly fewer losses.
-Russian people are in no way immune to winter and starvation, the French (and later the Germans) did not plan properly and suffered accordingly, no excuse in blaming very predictable conditions (even if they played a big part).
As for Total War:
-Russian infantry probably were the poorest shots when compared to the other powers but in no way worse than the Poles or the other nations. In fact the only country that had significant musket practice was Britain. When compared to other qualities, such as speed of march, discipline and desertion rates they were at the top or close to it.
-For the period covered in Total War the population of Russia was smaller than that of France, makes no sense to portray them as a 'horde' nation.
-Russian artillery was probably the best in Europe fielding the most guns, the best guns, the best sights, the best horses, reciving some of the best leaders, training and doctrine.
-Its also not possible to mention Russia without talking about its light cavalry. Maybe it was not the most disciplined but it was very effective at its assigned role of screening, raiding and scouting and only the authentic Hungarian Hussars could match it. In 1812 the French never really managed to counter it or break its screens to see the location of the Russian army.
-I would say the big weakness of the Russian army (and several others) were its officers, in particular the difference between being educated in French or in Russian would hinder communication.