IIRC it's only certain factions that have new ships available once the compass has been discovered (Caravels? Or do you have to wait until 1205 for them?). Certainly for the Muslims you can build dhows and baggalas before the advent of the compass and nothing better until gunpowder's been discovered.

Either way you won't be able to upgrade your dockyard (level 2 building) to a shipbuilders guild or master shipbuilder until gunpowder has been developed and you've built the necessary foundry upgrades in the province, which means you need a citadel/fortress there too.

That's a lot of extra building to get some fancy new ships you don't really need (weight of numbers seems to more than compensate for tech-level when it comes to navies, especially if you've got a few decent admirals and do most of the attacking).