I don't know if I would call it really good, but if I were to ever write a novel the setting would be dark fantasy like somewhere between the middle ages and the modern times where most men of the protagonists society are about to come back from a long war, but they also bring back a mysterious illness.

The protagonists were just too young to have gone to said war, but maybe an older brother did go, maybe he fell idk.
At some point the father comes home, but what was supposed to be a happy occasion turns darker because he is changed by war.

There has to be some form of secret society that has something to do with the illness or the lack of a cure for the common people.
And the young protagonists will have to deal with that situation due to circumstances and not because they were chosen or secret princes or something like that.

And I am a sucker for happy endings so while the novel would be rather dark as a whole, the ending would see a dramatic change to society with at least the potential to get better.
I think times of change make for good fiction.

I will never write that novel though, but just maybe I might get to use the setting for a TTRPG campaign some day.