Your system is great, and can add an epic feeling for the end of this campaign.
I'm translating it in French (I've alreday made the map), and I have a question :
When a unit cannibalize an other, what happens with the hit points...
For your example :
- 1 unit of Resistance Foot soldier with 4 members, hp 0
- 1 unit of Resistance Foot soldier with 6 members, hp 4 (it was derouted one day before, and heal 4 hp = unit CR)
If I form 1 unit of Resistance foot soldier with 10 members : 2 hp ? 4 hp ?
If I form 2 units of Resistance foot soldier with 5 members : the first with 1 hp, and the other with 3 hp ?