Material Instance Question?

I want to make sure I understand material instances correctly, for this example I will talk about, say, Brick and Steel. For brick I will have a moss texture that gets vertex blended over the brick with a blend mask. For steel I wouldn’t have any vertex blending on materials. Would it be a good idea to use the same material instance for both of these materials, and just ignore the vertex blending for the steel? Or is that a waste, and it would be better to have its own parent that it would share with other materials that don’t use vertex blending?

So I figured it out by using StaticSwitchParameters, which help turn things on and off, which is a huge help. But I have run into another problem with those.

So I am working on my master material, and I plan on having 3 vertex color channels usable, my only problem is, I can’t figure out where to place my static switch parameters in order to disable them and enable them. If I place them right after (as shown in the first picture) then my textures are overwritten by the blend textures unless I enable vertex painting.

I am trying to figure out how to place them, to disable the lerp’ing between my base texture and blend texture so I can leave the vertex colors disabled until I need them. I am not the best shader artist, so I could be overlooking something so simple here, but I need some help.

I tried doing this:

But then it makes it so I have to have Green enabled in order to paint Red, which isn’t what I want, I want each channel to be individual, and able to select only 1 channel, or all 3.

NOTE: I only have red and green set up now, I want to figure this out before I set up blue.

Hope to hear from someone, thanks!