I was planning on making a minor noble from another land (not one on the map), who's trying to essentially play "puppet master", and control people without them realizing it.
Do you already have 10 of those?
While I am not a GM, I do believe outlanders are vetoed. As far as has been established thus far, travel between the known world and other regions is either not known of or altogether impossible as far as the current means of transportation go.
I am a GM, and outlanders from the rest of Iitu (the planet, and no I didn't name it) are vetoed. You can come from any land on the map - Adranic, Altanic, Eldanic, Haegar, Duluk, Saelradian, Ralkarian, Ampyrian or even Selenid. The important thing is that you start and largely remain in Windheath. If characters are required to go outside of Windheath or its immediate neighbours, that will likely be a result of a major event such as a crusade or foreign invasion (i.e. lots of players will be getting involved). Otherwise, gameplay remains within the country and its immediate neighbours.
There's not much reason to come from beyond the Blessed Lands, actually. There are plenty of cultural archetypes to choose from and most of the cultures are deliberately unwritten so players can write them. See the
Lore Thread for details. I imagine you can accomplish most of what you want with those lands, but the rule against outlanders is to keep things within the scope of the game world and partly to prevent any visitors from the Storm Coast turning up...
Landed nobles are more or less taken up, but spending a character point on the Noble trait still grants you the legal right to raise a personal guard regiment and the ability to marry higher nobility. I'd rule that to be a Baron or higher you need to spend a point on Noble; lay knights don't need to spend a point on being of noble blood and personage. That said, you can always spend the point on something else and be a non-noble (or bastard noble) courtier - or disenfranchised noble, like my own character.