If it's just setting the room up with simple cobs and making each grow relatively the same, you get two more 3500ks for the corners, and then split the sides with two 2700ks and two 6400ks. That gives you all the power and solid balance in spectrum. UV-B and the deep and far reds, IR are what you need to figure in to veg and flower. As you probably know, getting more blue in spectrum with high UV-B concentration triggers higher terp production early on in veg, and the. If more deep and far reds can Ben introduced during the stretch, the resin and oil production also improve. Just be aware of this when choosing what you want.
I personally didn't want to invest a lot at the time I started and went with cobs as a base, I have 4(two 3500ks and two 3000ks- all around 75w each from the wall), one blurple with veg and bloom switches at 70w each and 140 total, and a qb board chinese copy pre made light made by Carambola and Vander Lighting. Great light at 215w wall draw, and super spectrum to get terps popping like crazy(kind of a pink light with green, blue, UV-B and IR lights on it. It has to get closer to get the ppms where it needs to be, but this light is my favorite to use for flowering a plant.
Cobs are great bro, but they don't do it all.
If I were you, I would get a couple more cobs from
@BigSm0 to even out canopy, then find a couple booster lights with some extra blue in one and red in another. That will allow you to tinker with spectrum more and get the best from each individual strain IMO. Some will probably disagree, but I believe spectrum and intensity is where you will find your best yields and quality.
Good luck!