MM, I assume you've got some gear in your frame pack as well, otherwise seems bulky for just a portage yoke IMO. And does your pack frame's top brackets nest into the gunnels? If so, don't they move if you bump into things like overhead branches, changing the balance? Got any pics? I know you usually puzzle things out pretty good.
I've got the Gen 1 of the Wenonah model that attaches to the gunnels and it can shift too if I bump my boat into things while carrying. It is plenty high enough to see well and still carry a pack on my back, for me it's a small blue barrel food pack.