Main drive tray and complete 24v electronics

After several test drives the drive tray is more than powerful enough to drag around 60kg or more weight, 24v makes such a difference over 12v. The next part of the build is the hardest as I still have no idea what this droid is going to look like. I was thinking about a mobile version of Orac from Blakes 7, sort of technical looking with lots of flashing lights and circuit boards. I was also thinking about a modification on the Wall-E droid but my own design with wheels and not tracks but again I am not sure.
The obvious choice would be a mouse droid but that is to easy, a scrubber droid would present a great challenge but still a bit to simple??????