ed, i like plinth blocks to "visually" sit on a supporting member......plinths, columns-n-capitols all throw back to early support systems so our eyes and brains have been trained that a column and it`s associated parts must be firmly rooted to the earth......in the case of cabinetry there should be a direct line to the floor of the room. setting columns directly over drawers or doors looks odd to my eye.....the size columns you`ve drawn fits well with the unit, they just appear to me to be unsupported.......tod