Re-creating plywood

Noel, wanted to thank you for such a great material! I’ve been playing with this to great effect. I had a question for you, I am working to beef up the realism of the material you provided and am looking for some pointers on how to add one more feature. Your awesome material alternates between colors on every layer, one color to another. This is perfect as this is how plywood appears IRL. I would also like to bake in color variations horizontally into each layer to achieve something closer to the variations illustrated in the second photo. I am a real novice to blender, my rookie thought is to create two “levers”. The first is a broader color shift of less contrast randomly along one layer. The other is a tighter color shift of higher contrast to create knots, both randomly placed among the layers as pictured.

I’m coming to you because I have literally no idea where to start as I have almost 0 understanding of how this material is actually calculating and am just learning as I go! Thanks for making this.