You are re-stating well established facts as if they are new jewels, just discovered.
No-one has forgotten that the victory in the Peninsula was due to its long coastline, the Royal Navy`s command of the seas and the fanatical resistance of the Spanish and Portuguese armies and population.
If N had put 500,000 more troops into Russia in 1812, they would just have been 500,000 more corpses, killed by his failed supply system and the fanatical resistance of the Russian populace.