I have the broad arc planned out (including tentative chapter names). In Game 2, Stormwright, the tide of rebellion will sweep across Shayard, and you’ll spend much of the game in the capital. In Game 3, Omphalos, after a brief return to the Rim you’ll begin visiting other provinces (if you choose – alternatively, you might visit other parts of Shayard to consolidate your authority there) and infiltrate the Hegemonic capital of Aekos. Game 4, Downfall, will lead up to the siege of Aekos and the collapse of the Thaumatarchy in its current form.
Game 5, Hegemon, will see you trying to consolidate some sort of post-Thaumatarchic order in relation to up to thirty other factions. The ambition of this plan has been noted. 
Your “big bad” by then will vary based on the choices you’ve made to that point.
Probably not, I’m afraid. Any time I do a name change, I have to store the old name, in recognition of the fact that not everyone will switch over to calling you by your new one. But you’ll be able to pick an alias, which many people will call you by. I hope that’s some satisfaction.