More than likely, you are not going to want longer rods for pulling boards. In my opinion, the longer rods are only going to get you higher at the boat to clear other gear. The issue would be not having enough backbone to pull the boards effectivly. I run 7.5 and 8.5 rods and as many as 10 at a time. For salmon, we run heavier 8.5 and 9.5 and 10's.
The best rods i have found are the gander mountain angler series with trigger. Non telescopic in 7.5 and 8.5. I use these tournament fishing. Ensure they say Planer board on the rod.