You're L style double beam bumper is fairly light as it is. The RS style USDM one is nearly twice as heavy as it is a perimeter frame & has a heavy bar along the bottom. (I had both to compare)
I have the lightweight bumper now & the only thing it does for me is remind me never to rear end anyone. I keep the standard one around just in case.
A near no cost improvement to weight distribution would be to relocate the Battery to the trunk. It weighs a ton & is about as far forward as you can get. By moving it behind the rear wheels you are doubling the effect since the weight is removed from the front and duplicated in the rear. And it costs you what, a set of wires & a box?