Hi Jon,
My tuppence worth: while I understand that making a beautiful workbench can be a worthwhile project in itself, in my view I want something that's strong and sturdy, moveable, but relatively simple to build so that I can get on with building other stuff!
The workbench I'm planning to build will have:
- a strong frame, probably 3x3 verticals and 2x4 horizontals
- for simplicity probably just bolted together, or possibly half lap joints
- retractable castors, I quite like this design for ease of use: https://www.youtube.com/watch?v=RRpVr4nwt9g
- a Ron Paulk top (https://www.youtube.com/watch?v=Bt77_jugVZs), but probably only 800x1400
Here is a great free resource for building a roubo-workbench the hardware is crazy money but take the dimensions and construction of the bench and improvise with the hardware.
I am planning some day to make this bench. He uses hardware to connect the rails I might just use traditional joinery. and my tail vise will probably just be my record bolt on vise with a thick wooden jaw that can take a bench dog to hold planning material not as sexy but will work. Like the look of the leg vise . But this can be done by using a vise treaded bar off axminster for reasonable money.