Currently only the canvas decal (as far as im aware) has a shine value slider. More canvas items, especially cubes, would be great with a shine value and would it would add a lot of versatility to different textures. It would also help trim down on overall object counts in condos that use decals exclusively for their shine values. For example, in my case:
I’ve been using Lots of canvas decals with a full black texture, pushing them down into the floor (which makes them transparent, but still keeps the shine value) to emulate wet surfaces, shiny interior walls, etc. but they can be pretty buggy and clip onto other objects that collide with the decals plane. (Ex: A couch will get the decal placed on the floor texture wrapped onto the bottom of the couch).
TLDR: Having a shine values on more canvas items would streamline building for any sort of shiny environments, make it less buggy, and id wager would get used a whole lot too.