I think it comes down to more realistic terrain. GG terrain looks like Dark Basic terrain.
If you look at games like Planet Coaster, their terrain editing is light years ahead of GG. You can EASILY create tunnels, cliffs, overhangs, etc - it's all voxel based and amazingly powerful and good looking. If we had THAT kind of power, GG would be unstoppable.
As I have said before, at a minimum, we need a stamp system where you have 'brushes' and stamp the brushes into the terrain - this would allow for erosion, riverbeds, lakes, strata, fractal mountains (much more realistic), etc.
Eventually, the ability to create in-ground items, like tunnels, volcanoes, etc. would be really great. For now, they have to be created as entities.
Mike
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