The entire point of the series is Voyager returning to Earth. If they don't do that, then the show was all for nothing.
And in my opinion, that's where the show went wrong. When your premise is 'the ship is trying to return to Earth,' then it's fairly obvious that the ship isn't going to return to Earth until the last episode of the series, thereby making all other attempts throughout the seasons of returning to Earth pointless, because you know they're going to fail.
At some point, they should have just thrown out the 'return to Earth' premise and randomly flying through space, and just settle somewhere and try to make the best of it. Because the 'randomly flying through space' thing just gets your ship destroyed every episode only to have it be miraculously fixed at the start of the next episode. The whole show just becomes unbelievable episodic drivel.
The ending of Quantum Leap was perfect.
And it was perfect precisely because Beckett never returned home. The premise went from "Sam Beckett is hoping that his next leap will be the leap home" to "Sam Beckett's whole reason for leaping is to make things better, so he'll keep leaping for the rest of his life."
Now apply that to VOY. Instead of the premise "The Voyager crew is trying to get back to Earth," imagine instead that it was "The Voyager crew were sent to the Delta Quadrant for a reason, and that is to make things better so that Janeway can form a new Federation." Now
that would have been a great show.
Except fot the fact that the attempts were half rear ended at best.
The Borg would usually only send 1 ship to assimilate Earth and UFP, and even though this happened already (and failed), you'd think the Collective would have send at least several hundred to thousands of cubes the next time around.
For Arturis star system alone, the Collective sent hundreds of cubes.
The Borg assimilation attempts at Earth and UFP at large seem more like: send one ship at a time... and if it works, it works... if not, we repeat again a few years later - but honestly, the Collective doesn't seem overtly bothered by assimilating Earth and UFP.
Seems rather stupid if you ask me especially with having a TW conduit less than 1 Ly waway from Earth (which is now destroyed).
The Borg's methods are more consistent with farming methodology.... by testing the UFP capabilities and technological evolution over time every time they send a ship... which still gathers data even if its destroyed.
Farming or not, their ultimate goal is to assimilate Earth and the Federation. Which, as you say, makes it very odd that they had a TW conduit less than 1 Ly away from Earth and they
didn't send a thousand cubes into it. But that's not because of any Borg 'farming' tactic, it's because of horribly sloppy writing.