Having Kronos 2mins away from Earth at warp is, well, idiotic. Why bother with a neutral zone when both worlds are now next door to each other? Klingon surprise attack by its entire fleet based at Kronos would be straightforward. It should be days away at least. Preferably weeks! It contradicts everything in Star Trek so far.
I guess you missed Enterprise's "Broken Bow"
And Deep Space Nine, where Earth, Bajor, Romulus, Kronos and Ferenginar were just a short Runabout ride away.