Well, I went with functional and easy.
I used the CNC router and tooling board at work to help me in this endeavor.
I had some extra 1/16" X 3/8" rare earth magnets laying around as well.
I milled out the bottom to make a perfect fit of the inner fan.
Then I used a 3/8 endmill to cut the seat for the 3/8" magnets.
Super glued the magnet housing on, then the magnets to the housing.
I machined a piece of polycarbonate to make the stirplate base.
2" flathead machine screws, nuts and lock nuts hold the whole thing together.
I fashioned a 1/16" think aluminum plate to mountthe potentiometer.
I used an inline lamp switch for a power switch.