[archaeolept]

1. enemy dominion decreases your income by i believe 1% per pt (and your own dominion likewise improves income by the same amount). However, undead dominion (ermor especially, but also carrion woods pangaia) will cause all of your population to die, thus rather affecting income from said provinces ;-)

2. upkeep is based solely on purchase cost and sacred status. upkeep is 1/15 of purchase, or 1/30 of purchase cost for sacred units. Supply used by units is based on unit size.

3. Cauldrons provide 50 supply for 20 nature gems. Bags of wine provide 25 supply for 5 nature gems. Thus, bags are twice as efficient as cauldrons. If you use dwarven hammers, the bags (@3 gems) are two and a half times as efficient as cauldrons (@15 gems).