Sorry but this isn’t close to right yet. Even if Russia manages to take the entirety of Ukraine it then has to keep it to class it as a win/loss.
It takes 10.76 troops per 1000 capita to hold a country. With insurgence that goes to 20/25 ( I think that’s what the US needed in Iraq and in a large part Iraq welcomed the US, that won’t be the case here )
The Ukrainians could make an insurgency far larger than anything in Iraq. A million trained troops and 2.5m reserve as well as a large chunk of guns an ammo given out during the run up to the election.
So Russia would need to have at least a million troops to hold Ukraine alone ( based on Iraq ). An insurgency with 50/75% of the population fighting against the invaders is something else entirely.