A usable workbench fits in two square meters. What matters is height, light, clamping, and power — not floor area.
Height
Stand at the bench and rest your palms on it: that is roughly your bench height. Most people land between 34 and 38 inches. Assembly work benefits from a slightly lower surface; precision work from a slightly higher one.
One good vise
A 4-inch bench vise bolted through the bench — not screwed to a thin top — turns a flat surface into a third hand. Mount it at the corner so long stock can hang past the edge.
Light and power
Put a task light over the vise, not over the middle of the bench. Add a power strip clamped to the bench leg so you are not running an extension cord across the floor every time you plug in a drill.
Storage within reach
Screwdriver and plier racks on the wall behind the bench, sockets on rails, and one drawer for fasteners in divided trays. Everything else can live further away.
Dust and chips
A shop vacuum with a floor nozzle handles most of it. If you sand or cut indoors, hook the tool to the vacuum rather than sweeping afterward.
Shop tool storage and measuring tools.