I haven't played with random leader/civ combinations yet, but I think putting any financial leader on Portugal is probably broken, especially on Archipelago maps. Make it HC for the most severe leverage (IIRC he is Ind/Fin), since he can build a cheap Forge, whip up the Collossus extra quick even without copper, and once the UB is built, that's five commerce per water tile. Previously only possible during a golden age. Since you get Custom Houses and the ability to transport any kind of unit at optics, this would probably make it worth delaying Astronomy for as long as possible. The overseas empire would be much easier to support with an economy on the scale that this would generate.
Again, this is situational to water-heavy maps, but Boudica of Rome is arguably equally situational in needing iron and being on a Pangea/Lakes/Flat map to get the full effect.