Nice!! =D

I see nothing wrong with the naming. I don't think your definition of "Bay" and "Sea" matters, realy. I'd call areas 1 and 3 seas and area 2 and 4 bays. But that's just me. Usually on my maps I call any body of water that's technically part of the ocean a sea if it's relatively open to the rest of the ocean and anything fairly enclosed a bay.