Sorry for the short reply. I had Christmas stuff going on. I'm in the final planning phase of a Vero 18 panel but started out with the CXA family in mind. I first took the desired wattage and divided it by the watts each emitter would use. I then took the resulting numbers rounded up or down and plotted out a node pattern in my grow area for 3 of the CXA variants. I didn't plot the 3590s so I can't say what the node distance would have been but I did plot a 3050 running at 66 watts. Node distance was about 13".
I ended up going middle of the road choosing 2530s, but then switched to the Vero 18 using the same grid. The node distance of that grid was 10" which in theory means better light mixing and light angle coverage (at a height of 12").
Based on that I'm guessing you could get a nice spread with 100 watt emitters at 16-18" or so. Define the base distance of a 60 degree isosceles triangle at various heights to get an approximate distance for nodes.
I picked 12" just cause it seemed like a good idea, and I'm not sure how to quantify intensity at various distances, and am working on the assumption that closer is better. Playing with a par meter and a few test subjects would be ideal.