@Deltakosh, I think @echadwick-wayfair is correct about displaying the individual channels of a texture as 0-1 (black to white) rather than black to channel color. In all of our DCC tools, when looking at the individual channels of an image, they are displayed as 0-1 and you have to rely on the UI to know what channel you are looking at. For consistency across the art tools, I would say we mirror that behavior.
The metallic map display when using a packed ORM is a little different as we will need to pass a flag to the inspector to know if the metallic map is coming from an ORM texture as it may just be an RGB stand-alone image as well. It would be very helpful, and consistent with the other behaviors of showing channels as 0-1 to be able to show the metallic map however it is loaded. If it’s an RGB stand-alone map, we display it as any other texture with an RGB and individual channels UI. If it’s coming from an ORM packed image, we show the blue channel only as a 0-1 image. That does change the UI around textures a bit as we will need to be able to distinguish a multi-channel texture from a single channel texture.
I also think there’s a need for a “solo” toggle button right in the texture parameters to display the current channel on the model. If we have the “all” tab selected, we show the RGB image as unlit on the model. If we have a specific channel highlighted, we display that channel as 0-1 on the model. While this behavior is present under the debug options, I agree that for debug purposes it is much faster to be able to quickly hop through the channels as you may want to look at both the 2D representation of the texture and render it on model at the same time for each ORM channel without menu hopping.
This is a standard workflow in packages like Painter where you debug your materials by displaying masks, normals, AO, etc. on model and in a 2D viewport side by side. The closer we can get to this, the more we parallel existing tools in use.