Can you edit the individual layers, or component, lineweights of a wall?
Yes. Here's how:
Go to the Visibility/Graphics window (type VV)
Click the 'Cut Line Styles' checkbox under 'Overrides Host Layers'
Click the 'Edit...' button
Change the Line Weight, Colour and Pattern of each wall funtion
This is something that you may want to save in a 'View Template'.