Sway bar brace?

Thoughts on sway bar brace that bolts under front sway bar while running larger sway bars as well?

A brace could make it act slightly stiffer if is designed correctly. A flat piece of steel would not be sufficient to make a difference.
Your intent is to stiffen the chassis, so you can not just put a piece of metal under the antiroll bar. It would necessarily have to tie into the front suspension to have a noticeable affect.