I already have afew, well actually several great mods already. But Im hoping one or more of the great modders out there will pick up and work on these ideas I have since I have zero modding skills myself .... Ok so heres my Ideas

1). A dead corrupt word ( Heavy dark colors.. Dark greys, Dark Red, Burt Orange, Rust brown, ect... with pale milky colored water, and radioactive green miasma.) The Fungal terrain could work well for this -or- if its possible perhaps new terrain tiles all together
...... the terrain coloring I know is possible even if new terrain tiles arnt because I use the Visually Distinctive Terrains Created by Cousken '