[Blaster86]

I always felt the Borg logic was that the Federation offered so much in regards to numbers of different species as well as unique technologies it made them a very tantalizing target. The other Alpha/Beta Quadrant empires, while close to equal in power, were much more singular in their makeup.

I think by the Voyager/Post Voyager time period, the fact that the Federation appears to be a major road block that the Borg have struggled to overcome, the assimilation becomes a priority because "holy #### can we imagine if we assimilated this? We'd be even more unstoppable!" Also if they take the Federation, the rest of the Alpha/Beta Quadrant is pretty much a cake walk.