That's pretty much how I see what happened in "Q Who", too, with regards to the baby we see. Not a clone, but a genetically engineered offspring. They might well do that because of the aforementioned genetic problems inherint in the replicative fading. This could be a "work around" for that problem, taking eggs from a suitable female and sperm from a suitable male would quite possibly give you something close to a cloning process - "organic cloning"? - each time you processed the inception. The only thing you would likely have to worry about is mutation in the early stages of the growth period. Of course, you'd be limited in the number of potential clones
Even more specifically, the God of Lies in "Q Who?" suggests the Borg are only interested in technology.
And even if Q was being serious for that rare once, his comment about the Borg interests need only apply on that single moment in time. The Borg there could have been sated with assimilating the J-25ians, and would only have mild curiosity towards the E-D.
Certainly we can't take Q's comments or Riker's observations and interpretations of the Borg as authoritative in any way. Even Guinan's insinuations may be colored by her hatred. This is the first time our heroes meet this radically different species, after all - they are bound to get a good number of misconceptions that won't be sorted out until much later.
I don't know that I'd call those early comments misconceptions, exactly. While certainly colored by the individuals viewpoints, they all seemed to be dead-on from what we saw on-screen. Even Q's comments seemed to back up what Guinan said with regards to the Borg.
I also agree that they've likely been very much as we saw in them from both TNG thru VOY, w/the "variations" being more a matter of mission directive than anything. Of course, I didn't watch the last season-and-a-half of VOY, so don't know what else was revealed. The only episode I saw from season 7 was the last one, and I was mostly disinterested in it after the first 20 minutes or so, having already figured out the plot and how the series would be most likely to end.
Even without "reimaging" TNG in any way, we could say the Borg there were always the same as in VOY. They assimilate Picard by sticking a tubule in his neck, at which point his skin color changes. They could have done the very thing to Riker, Worf or Crusher if they had reached hand-to-hand range - but they didn't, except with Data who couldn't be injected, and Worf, who managed to grab the Drone's arm long enough to prevent the tubules from piercing...
Worf the Bad Assed Klingon! I imagine he'd find a way to take himself and a dozen Borg out if they managed to actually stick the nanoprobes in him.