It's so funny you mention that because I was thinking about this in the shower last week... on the current controller, say: d-pad moves brick,2 buttons move up and down, right brown townog stick rotates bricks, left brown townog stick moves player, a 3rd button is jetpack, holding down left trigger activates brick selection: left-right moves through slots, up-down cycles through bricks/colors (like the mouse wheel inTBM/RTB), left trigger press-release by itself changes between brick placement/spraycan, right trigger is like left mouse button.
Would be AWESOME.