With each appearance of the Borg, they got more convoluted.
First, they were bees. Technology was their pollen. Humans were ignored, just like a bee would ignore you until you swatted at it.
Then in BOBW, they changed by assimilating people. Yet they retained the "they will ignore us until they view us as a threat" part of the Borg, which no longer makes sense if their goal is to assimilate PEOPLE. People became the "pollen."
Essentially I share your criticism, the introduction of the Queen Bee in ST VIII (ALIENS anyone?) didn't help to make the Borg more interesting, IMHO.
Where I cannot agree is your conclusion regarding BOBW. In "Q Who" the Borg suddenly assumed that the Federation had something they didn't know previously: "Q drive".
They pulled the data from the ship's computer and still found nothing. Apparently they had to resort to other means to access this information (which of course did not exist) and started to assimilate and set course for Earth where they expected to get the "Q drive" information. Just my 0.02 $.