In the earlier versions civ2civ3 terrains were adjusted to replace some terrain converting irrigate and mine commands to extra building ones, and vice versa. I don't know if that indicates that there had to be compromises. If yes, it might be a good idea to revisit those things for freeciv-3.1 where Cultivate and Plant are separate activities from Irrigate and Mine, and they are not mutually exclusive any more.
In the earlier versions civ2civ3 terrains were adjusted to replace some terrain converting irrigate and mine commands to extra building ones, and vice versa. I don't know if that indicates that there had to be compromises. If yes, it might be a good idea to revisit those things for freeciv-3.1 where Cultivate and Plant are separate activities from Irrigate and Mine, and they are not mutually exclusive any more.