One thing I wondered, was why Lore's Borg didn't have adaptive powers anymore. Phaser shots killed them (though the FX used made it seem like their armor deflected the energy somewhat) all without any adaptation.
Otherwise, yeah his Borg were more effective at combat than regular Borg.
The main reason being that if the Regular Borg fought like that, they'd be even more overpowered than they already were.
I think the Borg can only adapt when they are part of the collective, the Borg are stronger when part of the collective, take a drone out and that drone becomes weaker. The adaption comes from the fact the group consciousness can analyze an attack that felled one drone and counter it with the next drone. Drones outside of the collective do not have that ability.