Barbs are there until the end, unless you eliminate all coastal "fog-of-war". Barb Galleys and triremes will still spawn and follow the coast. However one Caravel or Galleon, 1 north & 1 south, should be enough to eliminate any that come near.
I don't know that I've ever seen a Barb Caravel, or newer ship.
I've been going over the save and still working out the details but first impressions are we need to produce our remaining military and then switch to science.
We need to worry about our own continent before producing Galleons to get to the other continent. I suggest building mounted units that can be upgraded to Knights, Maces/Pikes, and Cats or Trebs.
We will also need to do some wonder building to get the National Wonders.
Gandhi will give us Eng, world map, and 10G for Astro. The other civs want Astro, or several techs for Eng. I think it's worth the price to get Pikes and 3 movement. What are we willing to trade?
We also need more Workers, lots more Workers
Cities:
Some considerations: our cities are, for the most part too small. We are against the Happy cap in Fifth and Marbles. We either build a Temple to let them grow or use the excess food to farm GP. We still need some military so Fifth could build a Temple then Knights. Marbles could work on GP and/or Galleons.
Fifthburg - Temple (2T) or Galleons (2T)
Marbles - Temple (5T) or Galleons (4T)
Stoneopolis - Galleon (15T) or Kremlin (88T) ????
Engineering - HA (3T)
Parma - Forge (12T)
Far Canal - Forge (25T)
Ulundi - Cats (4T) or Colesseum (4T) for Happiness
Nobamba - HE (5T) then LH (4T)
Nongoma - CH (6T) A CH will not be need once we switch to SP, so perhaps a Wonder or Military or more likely, Workers.
Santerem - LH not CH
Leiria - Library
Evora - LH
War - Coimbra then Opporto. We need to get our military to the front a lot quicker.
I'll try to get a detailed plan together tonight and play tomorrow night, unless there's no comment.