Will we get to see a ship based off the same modifications as the Narada... loving the Romulan, Borg fusion. It looks awesome.
No - for the same reason as the JJ-prise/2009 Enterprise won't be in the game. Paramount owns the movies, CBS owns the rights to the TV series.
Crypric has a contract with CBS but not Paramount, therefore nothing from Trek 09, or the upcoming new movie, will feature in STO. And I don't expect that to change since the cost of obtaining consent from CBS and obtaining a contract from Paramount would very likely cost an absolute fortune and would likely have little return.
Thankfully, since in my opinion the Nadara is ridiculous.
Countdown is a licensed work itself, so at best the same rules as getting ships from other Star Trek games apply. And as its licensed from both Paramount and CBS, things might be even more complicated.
Honestly, the pre-retrofit Narada isn't distinctive enough to warrant that when we're probably talking about a Tuffli-like mini ship (it was the Borg upgrades that made it start wrecking fleets). A knockoff would serve just as well.
The Kelvin's saucer is about the size of the Constitution's. The JJ Constitution is supposed to be slightly larger than the original, but with bulkier engines (There is the shuttle scene that would require the ship to be much larger, but every other shot with a scale reference requires it to be much smaller than that shot did), putting the Kelvin a bit bigger than the Miranda.
With that scale, the Borg upgraded Narada is not quite as wide as B'ger and about half as long. Big, but we're talking tactical cube big, not Enterprise-J big.
If we go with the scale required for the shuttle scene (close to Galaxy size, making the Kelvin something closer to the Cheyenne or Nebula), this puts the Narada right about as long as B'ger and somewhat fatter. Large enough to break firing arcs and probably something that would have to be immobile, but still an order of magnitude away from the Enterprise-J.