Chronicles of Future Earth is Gene Wolfe's Book of the New Sun. It's weird. It's incredibly ancient. It feels medieval and old yet also weird and gothic at the same time. It's Jack Vance and Frank Herbert. Chronicles explores themes of decadence and decay and corruption. It also falls more on the fantasy side of science-fantasy.
Swords of Cydoria is Flash Gordon meets Chris Wooding's Ketty Jay series by way of French comics. Cydoria explores themes of imperialism and political power and social class structure. It's also more dieselpunk with a dash of pulp adventure and seventies sci-fi. Cydoria falls more on the science side of science-fantasy. It also depends on where you are in the setting. The City-States are the film Metropolis. The deserts of Eris are American Westerns and Firefly. Everywhere in between is good old Swords and Sorcery with blasters.
Numenera, however, is much more transhumanist, more avant-garde. It is definitely weird, but not in a gothic way. It also feels like a French comic book mixed with anime. It is based more on digital concept art paintings than on literary precedents, I think. In my opinion, there is no strong thematic thread to Numenera, no central gravity pulling it together. It is more patchwork and episodic. One thing I've noticed reading and playing Numenera is that you never see the same thing twice. Everything feels unique, or only found in a small region and nowhere else, which is what contributes to the patchwork feeling I get from the setting.
Personally, I like all three. Each provides a different take and has a different feel.
Chronicles feels more literary.
Cydoria feels more pulpy and cinematic.
Numenera feels more avant-garde and anime.
