they could try "Star Trek meets The Matrix"
Imagine a story telling about how the Borg came to be. A people much like ourselves except that they think it would be cool to be in an alternate machine reality
But what happens when they want more?
sounds very complex and quite interesting if done properly
I'm imagining a very artistic approach... anime-styled scenes... unconventional storylines....
But your thinking of it in too obvious of a way.
The Borg past and present is portrayed in a way that is inconsistant - so there is a mystery to solve.
The Borg supposedly wish to assimilate other cultures to improve themselves. They do so by attempting to totally assimilate the technology and biology of other races. That is self defeating. To explain, if they were to attack Kirks Federation and assimilate it they would never gain anything from the future, by
raiding it instead they could come back in a century or more and gain once more. So the question becomes what are the Borg
really after?
There is also the Borg strength and
weakness to account for. On the one hand the Federation always survives fighting them on the other Guinans people were forced to scatter across the galaxy to survive. The same Guinan who makes Q nervous with her power. How can a race that can scare the Q be defeated by the Borg but the Borg be defeated by the Federation?
It will take a little to get back to the Borg so be patient with the next section I will come back to the Borg.
Imagine instead the USS Intrepid NCC-38907 (Excelsior class) ship being launched on a very special mission (with a supporting fleet of freighters and liners etc) of indefinite duration. Survey for duplicate planets and cultures and find their origin. The Enterprise found planet IV, system 892 with a copy of the Roman Empire whose history matched that of the Earth Roman Empire but one that didn't fall. The Exeter found the planet Omega IV which was a total copy of Earth up to the late 20th century but more than a 1000 years older than Earth itself.
Other planets were found to have transplanted cultures from Earth such as the Indians visited by Kirk and protected from an asteroid impact. The transplanted cultures were moved by a race called the Preservers who seem to attempt to preserve human (and humanoid cultures). Searching them out would also be part of the Exeters mission.
Next there are the Ur-Humans the creators of the later races and just perhaps also the Preservers or their ancestors.
Finally there are the Organians, humanoids evolved past a material form.
The questions being:
1/ Who made the duplicate worlds and cultures?
2/ Why?
3/ What connection do these powerful and ancient humanoids have (if any) to the duplicates and humanity?
As the Exeter explores far outside the Federation they would encounter duplicate worlds other than Earth, Klingon, Vulcan and Romulan to name 3. They might even discover that the twin Romulan worlds are themselves duplicates of Vulcan that met early in their stellar explorations and merged into a united culture.
So what would the Exeter ultimately find out?
1/ The Ur-Humans are still out there, evolved past the Q.
2/ The Organians are the most advanced along the path the Ur-Humans want humanoids to follow and act as intermediates between the Ur-Humans and the Preservers
3/ The Preservers are an advanced humanoid race (possibly similar to the Talosians) and are well on the way to Organian levels and act under Organian direction to preserve lesser races
4/ The Borg are a tool created by the Preservers to
help save lesser races.
Under this outline Guinans people are a small step below the Preservers but were stagnating so the Preservers sent in the Borg (with Preserver enhanced powers to beat them) to disperse them and cause them to develop. The result is Guinans people have evolved further and the Borg only harrass them to keep them going.
The Borg attacking the Alpha quadrant do so because (like Sargons people before us) the Quadrant is on the verge of the next big technological leap and would destroy themselves in war (like Sargon) unless faced with a common threat to unite against. The Borg are that threat, difficult but scaled to be beatable with detectable flaws.
Perhaps a complex enought concept to last several seasons. It also could be based in a duplicate Federation and the Intrepid could meet the Enterprise NX-01 with Captain Archer in charge. The audience shock when they found there were multiple Federations would be interesting.
It would have the added benefit of curing some continuity errors as Kirks Federation need not be Picards or Archers.