The Infancy of a Workbench Design

I had a wonderful conversation with Kari a few weeks ago in which we both agreed that the space between the front & back legs of a bench does not need to be open (in line with the legs). That conversation confirmed an idea which has been brewing in my head for a few weeks: using panels in addition to stretchers between my front and rear legs. I think this will add both mass and stability to the bench.

After we talked I worked on some sketches of how to construct the legs.

The legs will be a 2x6 & 2x4. The double panels between
the stretchers will be 3/4" OSB on the outside &
3/4" MDF on the inside.
Today while waiting for a meeting to start, I sketched some more. I'm pleased with the way the design is coming together.

This shows a cross section of the bench construction.
Sorry the leg cross sections are backwards, that's
the order I drew them.
I need to do a little more research and then finalize it.

How is your bench leg assembly constructed?