Blocks & Decoration Allow walls to blend in with sloped blocks

[Battle Bee]

If you don't understand what I'm saying, take a look at this:

As you can see, there is a wall "overflow" going on. The background walls do not fit into the sloped blocks, and it looks bad.
So please, fix this problem. It's really hard to use sloped blocks for outside walls because of it.

 

[Akrasia]

Rather than doing that, how about adding a new tool that is similar to the hammer but it only works on walls? It would allow some really awesome backgrounds.