Yah I know, it is really tough to do... but I think I found a way ;p
I basically gave the galley to almost nobody, coded it as naval power (haha, cute way of saying I checked the naval power box), and reduced its transport capability to one.
I deleted the curragh, and restricted the caravel in a similar way.
The galleon is the first transport naval unit open to everyone (I considered making it the transport, but that seemed too cruel).
I also eliminated all goody and barbarian huts, and basically returned the barbarians to Civ2 status
-Barbarian Chieftans with 3/2/1 enslave to Barbarian Warrior, not wheeled, swordsman graphics
-Barbarian Warrior 1/1/1 enslave to Barbarian Warrior, not wheeled, warrior graphics
-Barbarian tribesman 1/3/1, immobile, +2 HP bonus, spearman graphics (meant to constrict movement without permanent terrain changes).
-Barbarian Galley 2/1/3, enslave to same, sinks in ocean, galley graphics (duh ;p)
Warrior, Chieftan, and Galley cannot skip turn, fortify, or stand sentry, and therefore must always move (gets them killed or active sooner).
All places which previously had a barbarian camp now have a BC minimum.
Galleys are liberally sprinkled over heavily traveled waterways (to simulate piracy and to decrease the level of oceanic movement).
They will remain a significant threat until metal warships, as their attack is equivalent to frigate defense.
Blocked off the Koreans from the mainland
Made desert and tundra impassable
Gave the Arabians preplaced roads connecting them to all areas open for settlement
Significantly strengthened the Keshik (blitz, db of 2/0/1, reduce cost by 5), to allow for the formation of a mongolian horde
Split India from Europe via careful placement of desert and mountain
Made the Urals impassable except at one point (defended by two Barb Tribesmen and a Barricade... might be a bit much)
Iberia is cut off from Europe by two Tribesmen in Barricades (one at N route, one at S).
Eastern exit from Italy is cut off by a Tribesman w/o barricade
Deleted Babylon and Sumeria (crowding concerns). May create a new civ in SE Asia, but I like the possibility of colonial warfare in the area.
Cut Egypt off from the rest of Africa (historicity).
I know that that is a lot of changes to your beautiful map, but my goal is to force the computer to develop in a historical fashion. So far, it has worked the way I wanted it to, but not perfectly.
I too miss the days of Civ2 scenario events. It makes things so much harder when you have to do EVERYthing at the start and hope that it all works out.