Thanks for taking the time to consider my late night rambling thoughts :P
1)Eeeenteresting.
2)If you do go this route, I think abstracting the zombies gained into different power tiers is probably important for striking a satisfying balance there without crazy overhead work. My main reasoning for this is that it's already underwhelming raising anything stronger than a boar because you know the zombie you get out of it is going to be strictly weaker. I dunno, could be just careful tweaking of the zombie stats over time could relieve this, maybe I'll tinker with that some on my next run :P
3)I agree with this reasoning and on reflection, I might have just been itching for more birds in the game in my sleep deprived state >_>
6)I suspected but I appreciate your confirmation, maybe I have a next tinker project or two :D
7)It's a small thing from player perspective but honestly one of my favorite things from immersion point of view about DF and cataclysm.