Voyager wasn't founded on the premise on being Star Trek Borg. It wasn't until season 4 they started showing up with any regularity. So that really makes your comparison invalid. Your opinion of that particular antagonist, is just that. Mine happens to be different.
By the logic of you saying, the Delta Quadrant has the Borg so there should be more Borg episodes. Well... couldn't you say that about any one of a dozen Alpha Quadrant species? That TNG should've had more Cardassian or Talarian episodes? Space is big. There can be more than one antagonist in a given area.
Either way, Voyager was never supposed to be -about- the Borg. It was supposed to be about a divided crew being force to work together. What we got was just a few brief acknowledgements of this early on, then nothing beyond a few people with funny rank badges around that act exactly like Starfleet people.