Just bet. I believe that:
1. Infantry (all types) - division (since 3-4 divisions forms army, 2-3 divisions it quite enough to protect real city). BTW, greek phalanx had 5000-10000 men, Legion - 10000. So like division now - 3000 up to 10000.
2. Tanks - brigade (80-120 tanks)
3. Artillery - division (don't remember how much)
4. Aircraft - wing. It should be 20-30 planes in wing, isn't it? BTW, most known US carrier Nimnitz carries up to 80 planes (20*4). BTW, in real life carrier planes is NOT the same planes like ground based. In real life it is impossible to base F-15 on carrier

5. Choppers + paratrooper - I don't know. Chopper unit should be able to carry paratrooper unit. I don't believe that paratrooper unit is a division, you need at least 400-500 choppers to be in one chopper unit

So it is more like regiment of paratroopers (1000-3000 men) and 100 choppers. But in this case I can't understand how regiment of paratroopers can fight full scale infantry division (but it can). Maybe it because paratroopers is "special forces"?
6. Chivalry - it should be division too.
7. Naval units. I believe we should destinguish between modern and old naval units. Modern - is one by one. So carrier is ONE carrier (with its up-to-80-planes onboard). Except transport. I can't imagine 4 full scale divisions in one transport... The same thing is about trireme. How many trirems we need to transport 2 full-scale legions (10000 men each)? Something like 20-30. Thats the number.
8. Nukes and cruise missle. I don't know. I believe 10. One nuke costs aprox like battleship, right? So in real life you can make 10 for this price.
Any comments?