I know this probably isn't graffiti, despite being done in that style, but if I came across graffiti like this in a place where it shouldn't be allowed, I'd say "Screw it just leave it there, it looks awesome and you can't deny it, and it also makes this thing look better, despite making the wall lose its rustic (is that the right word?), city-like charm." XD
Nice man! I'm still a toy so mine looks nowhere near that. I think once I get some real caps, I might improve. But I'm not sure. I'll just have to wait and see.