"About the river-delta thing: this is erosion and is in nature quite common!"
I get that, but perhaps being realistic shouldnt be the goal. Shouldn't the primary goals be something like:
- map makes interesting game play
- balanced
- easy for player to understand
- looks good
then way down the list at position 20:
- is realistic portrayal of earth
"what would make a beach instantly recognizable? Or a piece of mountain / unwalkable geometry?"
simple obvious consistent predictable terrain without unique obfuscating detail overload
like if you look at what the do in mapgen, looks like cliffs are a different texture. Plus the texture in the middle is a darker colour - you can instinctively get a feel for the chunks of land. so you can instantly play a map you have never played before, even if it quite complex.
i'm not trying to say that you should turn your maps into that. its great to have maps in your style and we should keep them. im just saying that its also good to have maps in the other style -> easy to understand. probably too hard to have your cake and eat it too?