Soldato
Actually 4th screen is centre (default) assuming you have a 7 screen setup. I highly recommend launcherpo. The dock is more versatile. you can remove labels, its smooth. Has a nice 3D apps drawer. Plus yuou can set the number of icons in rows and columns, in my case I have a 4 by 5 as you can see in bottom of 2 pictures.
The only thing I like about touchwizz over LP is the apps drawer because it is slightly transparent. Unless there is an option i've missed?