Why not use the ones they already have? There's no need to put more useless stuff in the game. I think there are enough. I use the X for stashes the double house for forges, there some I just don't use.
When I figured out about them I used the for certain things all the time so I know which one is which. If you have to draw each one on paper and write what your using it for.
Wouldn't you rather them spend time bringing things to the game that will inhance it? I rather them but time into bringing over new zombies maybe some new perks. Maybe even improve on the forge. Make it so it levels as items are smelted and made. Let's you hold more then the 30 k right now. I'm sure there are better things they can do then to put more icons in the game
Just my thoughts