Besides putting everything into a nice aluminum enclosure, replacing the linear voltage regulator - which burns three times as much power as the whole circuits consumes - by an SMPS (based on the old L4962) an over-current-protection and two status LEDs have been added.
(Milling aluminum is something else than milling wood. One cutter and nearly the front panel have been ruined. Don'`t know how to do it right, but very slow revolution and feed helped at least a bit. Maybe the cutter should have been cooled.)