Well generally the fish further up in the column are on the HUNT for food and tend to be more aggressive. That being said the fish further down are usually more lethargic and laying low. Now that is not to say that they are not feeding or wont smash a bait.

I dont really use BB that much anymore in my presentation but when I do I troll between .9-1.7 with 2-3oz BB and I generally shorten up my Harnesses. I have never ran my BB under a board so the rule of thumb I was always told to keep your line at a 40-50 degree angle and just watch the action of the pole as you troll.

As for your question about slower or faster well on this particular day its obvious that they were more active up in the column so the longer leads away from the boat and higher in the column were better then dredging the bottom. Day to Day things will change, its up to the crew to find were the fish are active in the fishery thats why when your trolling you set all your lines to different depths to find the activity.