my suggestion of putting the bench againsst the wall, was to save you open space in the center, incase youre tackling something big and need to move sheets and stuff around without having to lift them over tables and machines.
My other suggestion was to build another table that fits underneath the bench on castors so you can work on any side of a project, and have it anywhere so it can be pushed aside when not working on it and not in the way of anything else.
when space is a major factor during projects, every inch of open space needs to be free when needed.
I often push a few machines to one side, the next day I might have to push those same back to the other side, but its only a few minutes to move 4 machines, and the space makes me feel like Im working in a shop double the size(only feels like that, its still about your size shop)