[@RWDS]Um, isn't this exactly like my ongoing fantasy NRP?
http://www.roleplayerguild.com/topics/93983-fabula-elysia-medieval-fantasy-nationgame/ooc
Pardon if this may seem a bit of advertisement, it isn't.
I just say we literally have a 15th century like fantasy NRP already.

Mind you, it doesn't mean you are forbidden to make any more of these. Goddess, no! I just feel you might be more successful to pick a slightly different theme.
Steampunkish, Napoleonic, World War, Ancient Ages and so on.
There are many alternatives.

EDIT:
After another moment of thinking I guess 16th century would make the most sense. Age of discoveries is exactly a period which was rejected by my players as an alternative setting for Fabula Eleysia.
On the other hand you pretty much do that.
Anyways, I wish you luck with this game.