Happy New Year to you too.
I like the idea of the nobles having a "corruption" stat, something which makes some of them politically selfish, while others could be "honest" and vote more in favour of things which help their nation. Dunno if this should be a number like military politics, or if both of these should be packaged up into a "political personality" trait, so all nobles have a trait indicating if they are honest/corrupt/militaristic...
We're currently looking at plagues, so that would work well here, with the nobles needing to choose between what is best for them and what is best for the nation (similar to the "evidence discovered" crisis, where they need to decide which province to lock down). Corrupt nobles could always vote only to defend themselves, while honest nobles would vote purely to maximise the wellbeing of their entire nation.
The inquisitor thing also sounds good, with them being in some way opposed to corrupt nobles (so corrupt nobles would oppose the creation of inquisitors, and so as a result be beneficial to you, because they would reduce the risk to your enshadowed nobles). We'll need to think about that, though, as inquisitors might just make the game even harder for the player, without adding enough fun to be worth it. The game is already very complicated, so adding yet another threat to the player needs to be carefully discussed.