I've forgotten most of the space battles I've ever seen, including the one from "Identity, Part 2." The only space battles I really remember at all are the ones from Wrath of Khan and the two pivotal battles from Babylon 5, because they were struggles between people and personalities, not just swooping and swerving and pew pew pew.
"Best of Both Worlds, Part 2" was great, but not because of the sleep gimmick (which was cute, but not brilliant). It was great because of the character moments. The Admiral's controlled-but-impassioned rebuke to Shelby when she made a comment about Picard helping the Borg, the tension between the ambitious Shelby and Riker as he considers his own future while having to face the specter of his former captain, the intimately weary moment between Riker and Troi ("Seasoned!"), and, finally, Picard's stealth defeat of a hive mind that he should have had no chance against. It was a defining moment for TNG and Trek, despite what became of the Borg later.