I really like the temporary presents feature, I think it would be interesting to see an expedition with a similar trait-it feels like it adds to the diplomancy.
Dark knights can be turned into ordinary zombies by separating them from the base-using a hero might also work, but that would be pretty expensive. I hope you have fun archerbob!
Focus on gaining land and taking out nearby bases, only fight the zombies if you have a large numerical advantage, and use Roseline to deal with any bothersome dark knights.
Tantoney consolidate both upper towns. Do not face the southern pikeman head on, but wait until you can cut him off. At that point you hold the advantage.
PJBM
No, but it is possible to get rid of them by placing them in a location where a rival is likely to get rid of them, or even build more until you go bankrupt. I would be careful of that strategy however; as it leaves you vulnerable to attack.
I have checked, and it seems that as Ruffle gets more advanced it may be able to work on advanced content like this in the future-hopefully not too long, though.