Welding Tips and Tricks

So Im adding on to the shop next week so I can make room for another fab table and give me more room for the lawn tractor, golf cart, Onan generator and cabinets/shelving and the polaris Ranger. Its getting cramped in there!
This table will have at a minimum 1/2" plate top. Due to the position of my car lift I will probably have to keep it at a 4x8 foot print. Since I'm in the brainstorming process I figured I could benefit from others and what they found useful.

Most of the fab taking place on this table will be tube roll bars, rock rails and bumpers. My other prep table is on wheels and this one will be too. The last table I built was 5x16 at my old shop, it was 5/8" plate with 2x4 rectangle tube for the frame.

I'm trying to decide what I want to make the frame out of for this table, it will be on casters and have ability to be leveled when the project calls for it.

Any input?

The table that I'm using is an old transmission build table that my buddy has. He also had a sheet of 3/32" aluminum that he let me cut and put on top of the table to eliminate conductivity issues. If I have to weld anything that's gonna get really hot then I put a piece of 3/8" X 12" X 30" mild steel flat bar down on top of the aluminum to keep the thin steel and aluminum table top from bucking. Even though I often weld steel on top of that flat bar I have never had any conductivity issues with it thanks to that sheet of aluminum. When I was only welding on the table before I put the aluminum sheet on it, every piece of steel that I tried to weld would bond with the table within a few seconds and there was all kinds of arcing going on between the table and the work piece.
You'll probably save a few dollars if you use pipe for the frame instead of tubing. 2" sch 80 should be plenty strong unless you plan on sitting a car on top of the table. Heck, it'll probably even hold a car with a little bit of extra bracing.

NICE FRIGGIN SHOP MAN