Great map, i'll try it out in a very big sp game and hopefully in some mp games later!
In addition to #knownfeature "Volcano" you could also add the new dom3 sites:
#knownfeature "Desert" (+death/heat scale)
#knownfeature "Rain Forest" (+growth/heat scale)
#knownfeature "Tundra" (+cold scale)
for the deserts, jungles and tundras. That would be some nice features and provide some natural heat and cold in the provinces.
Some little bugs i found:
987 seems to be a forest but the map means its farmland.
382 should've farmland
461+481 have 2 mountain symbols, maybe this is intended!?