I'm trying to read as much as I can about the topic. So I've read over wikipedia and watched some videos and such. It seems to me, this method of plasma acceleration would be prime for space thruster applications. Right now VASIMR is using ICH rf coupling to accelerate their plasma. They should ditch that entirely and move to wakefield plasma acceleration if it's at all possible within in the context of their current design. I'm not sure about the math behind this, but I'm under the assumption that the closer we get to relative speeds with ion ejection, the higher the efficiencies are going to be for Electricity to Force conversions (assuming the coupling efficiency remains the same). So let's stop wasting our time with 0.01% c plasma excitation, and really focus on getting to 50% - 99% c. Whatever the electricity cost, I could really careless about, because if we can develop an engine strong enough for terrestrial liftoff, there will be limitless potential for where we can go with it and you'll really see progress ramp up!