Is it true Mountain tiles and river tiles are incompatible?, and therefore you can't find both adamantium and a deep river together?
Currently each 48x48 map block can only contain one feature (adamantine, a cave river, a chasm, etc.) across all Z-levels. So you'll never find adamantine directly above or below a cave river. However, they can still be found on the same map, since most maps include several dozen map blocks.
That's all different in the next version though -- there'll be layers of features on top of other features, and they'll be intertwined and stuff.
How and why did you decide to use Good and Evil to determine areas of the world map? In particular, what makes an area Evil? Dark magic? Radiation? Really deep HFS? More importantly, are all animals zombified because the area is Evil, or is the area Evil because all the animals are zombified? Will this zombification one day happen to towns or fortresses? Will acts of good 'turn' an area back to normal? Will undead infect others and spread Evil regions throughout the world?
Good/evil regions are actually getting removed in the
near future:# I.B: Remove good/evil regions and add more specific associations instead, requires some of the Creature Improvements below to flesh it out (part of Core94)
Your question is still interesting and relevant in that context, though. The "specific associations" are
religious spheres.