Ansel's return did not bring significant changes to the Hydral territory.
From the beginning, Ansel intentionally designed the political structure of Hydral to operate independently of him, except for some extremely important decisions. In this now mature system, Ansel does not need to intervene much.
In that world, the biggest issue with such a structure is that the ruler can easily be sidelined. However, this is not the case here—because even if Ansel does nothing, he cannot be sidelined.
In practice, various problems inevitably arise, and Ansel never expected his subordinates to be completely loyal and devoid of personal desires, solely dedicated to public service. This is clearly impossible.
The Hydral territory has never been a utopian society; it is simply far more advanced compared to other grand dukes' domains.
Marlina, who has been diligently working during this period, is well aware of this.