Yep im content with the current trunk size for this project, see Mach5's Red Beech cultivar thread, the one he got from Judy, I'd imagine it was started from similar material.
The reasons I chose the tree were for the subtle movments in the trunk, the branch structure and for the root flare at the base, see one of the pics that shows two strong roots on either side of the front. I feel like in the shallow container, the base will improve even in the pot as those roots get stronger and occupy the pot and thus the taper will improve too, there is one root coming from the front too. At the nursery I couldnt see the two roots, but I noticed the flare, I stuck my finger down deep and felt where the roots came from. Now had there been only one root I wouldnt have chose the material. This is one way of making decisions for the future. The 'flare' is a good indication there might be two opposite roots though.