Hey, Cloudio, your suggestion reminded me of the Game Freak HQ in the original Pokemon games. Ever since Red/Blue.
Especially how the director of the game would give you a diploma when you got all the Pokemon (well, all back then).
The talk about FFIV is also referencing their ingame "Developer's Room": http://finalfantasy.wikia.com/wiki/Developer%27s_Office
Nothing quite like breaking the fourth wall!
But tossing them in as random NPCs would be pretty cool. After all, Yoshi-P's Eorzean counterpart is the Wandering Ministrel!