Finished up the workbench. Made with mostly free 2x4s, with some extra 2x6s purchased.
Half laps everywhere.
Two sjoberg vises because I just have too much money to spend.
Dog holes.
Flip down casters.
Adjustable leveling feet that I designed and 3D printed. You can kick them over with your toe to adjust and get rid whatever wobble appears in that particular spot.
I've come to love building workbenches from 2x4's. They're (reasonably) cheap, soft enough to work easily, and you can essentially use mass to compensate for intrinsic rigidity. Maybe add plywood shear panels in strategic places. Even 1/4" plywood shear panel will beat most brace structures.
2x4s are cheap enough to try a design for a while & throw it out (or downgrade it to patio furniture) if it doesn't work. Soft enough to just plane a millimeter off the top when it gets beat up. If you invest in expensive hardware, move it to the new iteration. I've got like three of them now.