At the beginning of the week I started by topping the plant and remove a few fan leaves that were deep in the shadows. I repeated the defoliation a bit later as to not shock the plant more than it already is.
More issues this week, but I think I'm slowly getting to the bottom of it.
To start, I think the mosaic/two color symptoms that I've been observing are simply plant genetics as no matter what I do, this behavior does not change. What does change is the health of the plant when I start changing nutrients. By the end of the week, the plant was clearly struggling to grow new leaves (small, yellow/sad colors with slow growth). I already started feeding it normally, time will tell if I need to increase nutrients (currently on the 'light' feeding schedule at full strength).
I'm also fairly convinced I have a watering/soil problem. I ordered a new watering pot with shower head that will help spread the water instead of a big spout that just flooded the pot. This probably caused my runoff measurements to be off. I'm hopeful that a more gradual watering technique will give me a better understanding of what's going on in the soil (runoff pH + ppm) to make more sensible adjustments. My hypothesis at the moment is that the soil pH is wrong and that a lot of my feed water just goes straight to the collection tray.
Next week, I'll keep an eye to remove the leaves stuck in the shade and I'll install the ScrOG net to help spread the plant. I'll also see what the runoff gives me by changing the watering technique and see if I need to adjust nutrients further. I'm expecting the following week to be the last of veg growth, any more weeks and I'll have the same problem as last time where the plant grew dangerously close to the light.