This doesn't answer the question I and others are asking. You have given four criteria: "most distance", "least time", "least fuel expended", and "highest speed relative to Earth". You can only have two of them. Which two?I'm not aware of any other methods (besides a ~215km/s engine boost from earth surface to cancel the vehicle's galactic orbital motion) that can get a 10kg vehicle mass (containing a trapped electron) launched to >30,000km/s with respect to a trapped electron orbiting earth, using less propellant energy
Either answer that question or this thread will be closed for being too vague.