I personally do lighter work during isolation exercises due to the fact that I feel the muscle activate much more and have seen better progress. Back is a tricky thing to nail down how to work out properly and most people use far too heavy weight.
I alternate weeks between working thickness and width. I would say to try different things. Mix it up and try a week or two with heavier weight and lower reps. You never know what works for you until you give it a go.
For traps I do a lot of heavy dumbbell work and barbell shrug work, combined with heavy deadlifts. Deadlifts are a great overall back and thickness builder. You have a great attitude though with respect to taking criticism. We need more guys like you around here. Hope I semi answered your questions. If you have anymore feel free to ask and I will answer as best as possible. Best of luck!