i would love this.

i did see one person suggest just using the wallpaper with all the same colour to get a different texture on the wall- haven't tried it out but their screenshots looked promising

Yes please. High gloss in certain places/colours adds a sense of luxury whether white or black. I especially dislike that white is never really 'white' (ceiling/walls). The dead white (grey) just looks...well, dead (and old and dirty). Textures like the above, both inside and out would add a great deal of character.

I'd add to that, texture in cloth - towels and sheets rugs etc

I agree, it would be so fun

YES! Would love to see faux finishes!