My primary workbench is in my garage and space is an issue, I would love to have an 8 or 10 foot one but space has stopped me. I don’t weld on, or near it so my approach is likely different than some might take. I purchased one similar to the metal Craftsman ones with half of the lower part with drawers, other half with shelves; that served my wants for storage. But I wanted it heavier and a bit taller so I took some laminated beams about 3” thick and cut to fit the top and laid them flat. I then took some heavy oak truck decking and glued and screwed an oak lip that covered the beams and the edge of the original workbench real snug. I have had the decking for years and figured it was time to use it! It looks like a 5” solid butcher block oak top. I coated the oak with several coats of poly. This added about 5” to the top of the original workbench and a bunch of solid weight. I mounted my vise to the corner of the top and it is real solid.
I put extenders on the metal back/upper shelf that included a 2X6” horizontal “backsplash” at the edge of the oak bench top. I mounted a 2-bulb florescent light on it (put plastic protective tube covers on the bulbs) under the shelf that was at the top. I mounted 20 amp receptacles on both ends of the 2X6 and a switch for the light. Just plug it into a 20A outlet and I am set to go!
I ran across a scrap Formica laminated table top that I cut to fit and put on top of the oak top for a “temporary”, disposable work surface that is easy to clean. So far it has held up well, I guess 3 or 4 years. My son joked it was a little anal, like wearing a belt with suspenders.
My grinder is on a separate stand, keeping some of the mess away from the bench work area.