People,
One thing always puzzled me. Aside from the out-of-universe fact that sending the Borg in large numbers would spell the end of the Federation, and therefore any ST series wouldn't survive such an attack, meaning the end of the shows, I always wondered why the Borg didn't send more than a few cubes at a time to assimilate the Federation. I recall that Guinan said of the Borg in their first appearance something to the effect that they never do anything half-way.
The Borg were based in the Delta Quadrant. From that distance, which for the most part, the Federation wasn't capable of crossing without significant outside assistance (re: Q or some other highly advanced lifeform). So to the Borg, the Federation was a minor annoyance on the other side of the galaxy - almost as if they're playing with the Federation. To the Borg, the Federation's assimilation was inevitable, so they could have their minor victories - for every cube they destroy, the Borg have another thousand they can use, with more coming togeter all the time. The Borg consider, if the word can be applied, that they're unstoppable, so they can send one ship at the Federation and lose it, lulling the Federation into believing that they've done something significant while the Borg adapt to their strategies.
In a way, it's fairly ingenious - FORCING their enemies to become stronger and smarter, so that when the Borg assimilate them, they've gained more knowledge and information than they would have if they'd just left their enemies alone.
As to the OP's question, VOY made the Borg a bit less formidable, but they were still scary at times. I think the scariest was in the ep with the Borg offpsring of Seven and the Doctor, the character called One -- if he were assimilated, because he had 29th century technology in his construction, the Borg would become unstoppable. That sent chills down my spine.
Yeah, just the thought of the Borg getting their assimilation tubes into technology five centuries ahead of what they've got is terrifying - it's almost a textbook example of the Temporal Prime Directive and shuts me up about it for a minute as I consider that future knowledge getting into the hands of the Borg. Remember, One came from just a mobile emitter - that's not exactly a weapon, now is it? And he managed to walk all over the Voyager security teams and the Borg on the sphere. Just think about the Borg having that power.