It seems that the acoustic version is the favoured route forward
Mind you a few swirling synths, delicately added to the mix, would bring out the spacey, out of this world, comet theme, without changing the overall feeling too much either.
I think you could also add much more emotion into the chorus: by flattening the chorus and taking it down the scale, so it becomes a little bit sad, more emotional - and this also fits the idea of a comet, because it arrives in a flash of excitement, but as it fades away, the emotion changes to sadness......