Well, initially, yes, but hypothetically, if there was a fleet of ships navigating the solar system over a long period, not all would have to return to earth before blasting back to elsewhere. You'd just have shuttles to take people and things to and from earth.
Ah, I see. So you'd still have to boost resources up from earth (propellant, water, etc), but you wouldn't have to reboost the people and craft. I always hear of the moonbase being a good first step, which it really wouldn't in this scenario, since it assumes a fleet of craft able to explore our solar system even semi-efficaciously.
And even when we do have such a fleet, a better scenario than a moonbase might be to have a space station with some artificial gravity. That way the astronauts wouldn't have to return to the earth or the moon to escape the effects of zero g on their body. And also, you'd use a lot less propellant than even at the moon, since all you'd have to do is put yourself in a transfer orbit to head off exploring.
That's basically it. Electric propulsion in general has REALLY high ISP(like a miles per gallon rating but for rockets), but accelerates incredibly slow. You can still reach really high thrust values, it will just take you 10 years to do so.
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I ate a hooker half a bottle of knife.