Well, here's the thing. Sooner or later you're going to row backwards, or do rapids backwards, or sideways, cause, you know, poop happens.
I decided years ago the best spot was just aft of the middle; gives good control all around, and weight distribution is as much about where you pack the beer as where your fat butt is sitting.
And if you row, you know your power is in rowing backwards; if you're just aft of the middle your directional control is better than if you are sitting dead center or in the front.
In my opinion.