I like most guys started with the plans for the "EAA" work tables then realized I wanted to be able to clamp stuff down, and wanted to utilize the materials a bit more efficiently... and for a couple dollars more with a couple of dimentional changes I could use all the lumber/plywood/MDF nearly perfectly and have two beefy tables and a third, strong but not beefy table... I put my dimpler on that one... (I was a building contractor for a few years, so I 'know' I can think of a better way

)....
So I'd recommend you look them over and tweek them to your needs. I wish I had thought through putting some sort of castors on the feet to make them move easier and probably will retrofit one or two of them with castors.
And while I'm not a 12 builder I think you'll find that the EAA plans emphasize level and straight construction a bit more than you'll need on a pre punched aircraft like the 12... one thing the EAA plans will emphasize that I feel should be followed is glueing all joints... I personally used a finish nail gun to tack the glued joints together with titebond wood glue... then hit it with a couple of screws... went together a lot faster. Some of the bigger joints got a framing nailer nail or two then screws, and glue.
So far on my 10 about the only part I had to make sure the work surface was very straight and level on was the trailing edge of the rudder...
So if you are just starting out... start and move forward they don't have to be perfect you'll beat on them, prime them, drill them and more... Whatever you do, remember to enjoy!