Cavalry are a small part of the Second World War, yet they were used, at times very successfully. I am requesting that Cavalry be a new unit. It has the properties of stealth, as they were mostly used to ambush in forests. They will act like offensive militia, though with a little more cost in food. It should be boosted for the Allied Doctrine as they used it the most and effectively.
Here is a link to the use of cavalry
Here is a link to the use of cavalry