On Xin Sheng...
Where COULD the backlash come from? All levels and offices of the capellan political apparatus were thoroughly under the thumb of Romano, opportunitys to organize any form of resistance was completely curtailed before Sun Tzu's rule. They were in no position to lash back when xin sheng came.
The mask? Sun Tzu's father was responsible for it before his rule, then an aging bureaucrat, with very little to gain from any sort of opposition, was named in his stead. Now yes, there was a rogue director with a short tenure, but thats the point, she was offed before she could become a threat.
The CCAF? With the reforms during Romano's reign, any possibility for a high level officer to form a personnal power block was basically curtailed.
The Warrior Houses? Ion Rush was a "suntzuist" from the start.
The prefecture and the house of scions? I don't remember anything much interesting about them during Sun Tzu's rule but its safe to assume they were in too precarious a position following the 4th SW to become a threat to the chancellor's position and wouldn't really have the time to organize themselves to become one in the short time span between Romano's assassination and the start of the Xin Sheng movement.
The nobility? A probably very large part of the nobility could do no other then keep their opposition to themselves less they be visited by the tax collector for years of neglecting their economical duties to the state (tax collecting, or lack thereoff, on the nobles in the confederation is as much a political tool as anything else).
And never forget how a fad can take the world by storm. If its well sold to the people and that there are no alternatives (for much if not all of the media consumed whithin the confederation is state sponsored), it would actually be rather easy to pass it with stunning approval.
The people? History teaches that the masses rarely lash back at liberalization (for, besides the whole "Han Pride" aspect of Xin SHeng, from what I remember of Sun Tzu's reforms, it was pretty much that: liberalisation of the socio-economic aspects of the state) when under a "totalitarian regime" (well...actually I'd say never, can't think of an example on the spot).
And as for "the current system working for someone", just whom benefitted from the romanoist system, besides Romano herself (and perhaps her thuggee supporters, whom weren't that much of a thing as yet back then)?
So pray tell, where could opposition to Xin Sheng come from? The thuggees? Now THAT would be confounding in disbelief (hope I'm using "confounding" rightly, but you get the point).
*Add-on*
Okay, an example of "the people" revolting against liberalization. So there was the Vendée during the french revolution, but much of their support was as much if not more due to distinct cultural aspects of the Breton people compared to the rest of France as anything else. Now the CC DOES have regions with cultural differences from the "norm", but they hadn't been re-absorbed by the time Xin Sheng kicked in.
*Another Add-On*
Again with "revolting against liberalization", this time in Spain. Now I don't remember all the specifics, but when the liberals enacted their reform forcing the church to sell off their "common lands" and instead of creating a middle-class like they thought and instead favorised big landowners (inevitably igniting the traditionalist, or Carlist movement ), the fact was that this was a VERY BADLY EXECUTED reform. Mary-sues don't enact bad reforms.