I'm currently creating a zone suggestion map for Germany, most of the suggestions in this thread that haven't been added yet are in this map together with my own suggestions, although I don't have so detailed descriptions of the zones.
I'm now at over 400 suggestions with atleast one zone in every city over 100k inhabitants.
Images at some zone suggestions:
Königsplatz and Fernsehenturm further away, Stuttgart
Völkerschlachtdenkmal, Leipzig
Basteibrücke, Saxon Switzerland National park