We are a Group of Urban Explorer, we do some Pictures in Abandoned Places, old Mines, Caves or Bunker.
My Englisch isnt the best but i try to explain what we search and what we didnt search
GOs and NO GOs
-Signs that looks clean and can be used by a Lawyer for example
-Sings that looks like a Flyer for a Disco or a Club
-Industrial look maybe with Gearwheels, Machine
-something with a Scull
-a destryoed wall with a sprayed Subground font
-a Mine entrance with warning signs etc
-it dont need to be symmetrically, it can be but it can be also a-symmetrically
You dont need to do 100% what i wrote, it only can be helpfull for your Ideas.
Maybe its also helpfull when you take a look on our pictures http://www.subground.info
Feel free with your Design
I try to give quick responses and reply all your questions