The thicker padding keeps your shoulders from digging into the backrest. Bonus.
Leaving an old weight bench outside for about a year, the wood had dry rotted. My oldest son wanted to start using it, but the wood could easily be broken up in your hands. Since there was no major rust or structural damage and I was given some free scrap "composite-plate" from work, I decide to repair the bench instead of replacing it.
Step 1: Replacing the the wood parts
Using what was left of the wood as a template, my son and I cut out the shapes with a jig saw. Salvaging the hardware and marking where the holes needed to be drilled.