This is quite an interesting story. I find the crossover with Startrek a bit strange. But you've married to imaginary worlds that I love, so kudos for that. I'm sorry to see Kim leave, but maybe that's necessary so Harry can get back to his world -- or does he? To fulfill the prophecy, it would seem an absolute essential. And the Dursley story about Harry and Dud's daughter, Annie, seems to indicate it too. The wizard's seem to have fled earth to the stars, and it seems the Klingons may know something about that, too.
Well, write some more of the story so I can figure out what's really going on! :)
Author's response
I'm glad that you like the story so far. Kim's leaving was not necessary to Harry's going back to the twentieth per se, but I used her presence to give Harry a "normal" high school experience. Her Breaking up with him, While I didn't experience it personally, heard of it happening more times than I care to count. I did 20 years in the US Army and that exact scenario seemed to happen to new privates and brand new 2nd Lieutenants.
Wizards going to the stars and the klingons knowing about it. Well some Weasleys did. But the Klingons being aware of wizards and witches not really. I promise that the whole thing is going to come out very soon.