Altering terrain ingame

[BrianB]

Yet another suggestion:

The ability to (late in the game) alter the terrain, turning land into water (digging a channel, perhaps to connect two seas, or as a defense against ground units), and turning seas into land (Dutch "Polders" http://en.wikipedia.org/wiki/Polder, http://en.wikipedia.org/wiki/IJsselmeer (on the picture: the "Island" in the middle was once sea. Other changes to the IJselmeer have been a giant dike turning the sea into a lake))

This would make huge defensive works possible (and perhaps unbalance the game if enabled to early) by creating moats en dikes to block ground units and ships.

 

[Haradrim]

Personally, I would love to be abel to build walls as terrain improvements. Also, it rivers could flood, it would be nice to be able to build dikes and levees around the river, which would also give defensive bonuses. As for massive terraforming, like turning water into land, I may see a use for it sometimes, especially for digging a canal, or closing up a narrow strait. I would like to see the ability to use workers on a transport vessel, like for building oil platforms, or as you said, building artificial land.