I agree Harrier. It comes very early and gives a rather great advantage (though are they able to take on transports). A Viking Culture should also have that ability with it's Longboats too as well then, and be able to take along troops. A Longboat should be available somewhere around 500AD, the Polynesian probably a bit earlier though possibly not as early as nations get to Sailing (and Piracy) is way early too in the tech tree). Maybe move the Sailing tech forward a bit instead.
I would suggest not changing it though but instead adding "Deep Ocean" and "Shallows" to the ocean terrains, allowing Poly's Catamaran to brave Oceans and Longboats to brave Deep Oceans.
Other sea vessels can have various other allowances and the double movement added to a lot of early boats now could have that on only Shallows.
Shallows being along the coastal line (but possibly not on ALL coastal plots) and if set to not be on all those maybe even have some kind of bonus yields (or a building, or be required for Fisherman's Hut and require Coast to build a "Fishing Boat's Wharf" instead that replaces the Hut so only one of them can be built).
Coast being either only on the plot outside Shallows or mixed in with the Shallows in the coastal plots.
Ocean being a few plots out from Coasts, more possibly on larger maps, less on smaller maps, and Deep Ocean filling up the rest.
Shallows might even negate the use of Submarines on those plots, and of larger ocean-going vessels.
All in the spirit of "more is better"!
Cheers
I would suggest not changing it though but instead adding "Deep Ocean" and "Shallows" to the ocean terrains, allowing Poly's Catamaran to brave Oceans and Longboats to brave Deep Oceans.
Other sea vessels can have various other allowances and the double movement added to a lot of early boats now could have that on only Shallows.
Shallows being along the coastal line (but possibly not on ALL coastal plots) and if set to not be on all those maybe even have some kind of bonus yields (or a building, or be required for Fisherman's Hut and require Coast to build a "Fishing Boat's Wharf" instead that replaces the Hut so only one of them can be built).
Coast being either only on the plot outside Shallows or mixed in with the Shallows in the coastal plots.
Ocean being a few plots out from Coasts, more possibly on larger maps, less on smaller maps, and Deep Ocean filling up the rest.
Shallows might even negate the use of Submarines on those plots, and of larger ocean-going vessels.
All in the spirit of "more is better"!
Cheers