I made some progress rebuilding mine this evening. This getting to be more along the lines of what I should've done originally.
I have it in the alcove deal at the head of the garage. This build is a combo of floating (bolted to the walls) and braced with 4x4 posts at the front.
The left side of it is made to house the shopvac with a short shelf above it.
The right side is set up to just be shelves.
I am going to add one more level of shelves on the right side.
Between the back and side 2x4s being lag bolted to the back and then the front and sides being tied into the 4x4s up front, it is already plenty strong. I still have some more screws to run, but it is taking its basic shape.
The **** wire shelf above the bench will be removed and I will build a built-in cabinet up there with doors to hold my power tools and cases.
The bottom of that shelf will be the perfect place to mount some lights to shine down on the bench.
I will probably also do either some tray storage system on the back wall, or I will peg board it and go from there.
So far, the dimensions are: 31" deep x 71" wide x 44" tall (from the garage floor level). Add at least 3/4" for the top sheet, and another inch to the depth, at the front in the form of an overhang. That overhang will have the top flush with the walls.
I am 6'5", so the height and depth are perfect for me. I am lucky that my size allows me to have a tall and deep work space.
A couple more screws and that last shelf, and it will be ready for its top sheet.