My preference is
Holden Decor Hadrian plain. It's also sold as Opus Hadrian plain.
It comes in three colours white, cream, and metallic silver each has a golden metallic fleck add. It's not an issue at all. The walls in the picture have just two colours washed over the cream paper and the gold fleck isn't visible.
The metallic paper takes a spray paint really well and the detail falls out with a light dry brush and or a wash.
For speed modeling.I normally just roll out about a metre and throw a couple of colours at it and let them do their own thing. Thevonly thing I do is move a little paint if it pools too much in one place.
I then just cut it and glue in place.As with this castle for speed I use it on every surface .Then I just lighting peel off tge surface detal and throw a couple of washes on in place for plastered section( not yet done in the picture.) It sound wasteful . But I normally use the off cuts from the larger areas of wall.
Another really useful paper is Wood chip (fine or extra fine) this has a texture very similar too a medium texture water colour paper.
It ideal for rendering at speed.Joints are easily hidden by over wetting the join and blurring the paper into its self.
It's quite useful as a road and courtyard surface too.
The trick with card and paper/ wall paper is to seal the edge otherwise it delaminates from the surface and it's constituent layer.I normally rub a little superglue along the edge( smoothed out with a plastic bag over my fingers

)
Doh'
Didn't follow the link to the video first.
It's the metallic Hadrian plain he's using for his board's
