After thinking about the vacuum cleaner test run yesterday, several ideas come to mind how to solve the problem of the vacuum stressing out the motors.
First I probably should re-gear the drive train. This will make it slower but will probably help it to handle the load better. Also the vacuum needs to be lightened around 50%. A good portion of it could be replaced with lightweight styrene.
And finally it should be finished to look like it came from "The Jetsons" cartoon.