Originally, the story arc might have run to three or four episodes.
“I believe that we should stretch out this dramatic line as long as possible,” said Moore in the memo. “I am firmly in favor of a Part Three and Four to the story. I think that the Borg invasion of Earth (and by extension the Federation) will give us an opportunity to do stories that will stretch our characters and inject new life into the series overall.”
Riker would have been the beneficiary of a longer story. “an extended stay in the Captain’s chair…would help to define his character,” said Moore.
The story would have evolved “into a deadly chess game between the master and the student. Piker versus Riker.”
Both memos can be seen at Mission Log Podcast.
Source: The Trek Collective