I am on of the developers of Wallch and we need a new icon for the application.
This is the current icon:
and it is the first icon that we used for the application.
The application has improved a lot since the first versions:
So, we thought that a new icon would be appropriate. If you want to sketch the icon, please post below. We would prefer the license to be under CC0 and uploaded to http://openclipart.org