The bungee system on the new Seahawk looks different when compared to HP’s. Do you think this is because Scubapro realized how bad the design was on HP and decided to re-design from ground up?
I really wouldn't knock it that bad. Yes the wing will slide back and forth, yes it's easily corrected while you're diving. I dive over weighted at times because I have too - the added air in the wing for an extra four pounds can be a nuisance but when I have the correct weight, there's minimal air in the wing and the bungees are less noticeable.
For me it's the feel of the shoulder straps where they connect to the waist strap - BP/W the connection is farther back and for me that's less comfortable than where the HP connects.
It's all a personal choice, dive what you like and feel comfortable in!!