While the general idea and premise for the story was interesting, I found this book difficult to get into, mostly because I (personally) found the main character almost impossible to connect with or care about. Now, this is an entirely personal problem, so naturally if you're interested in the book my personal apathy toward the character shouldn't disuade you. However, I might recommend definitely reading the sample chapters of the book before buying it - just to get a sense of whether or not you'll like Eon.
Anyway, my basic problem with Eon was that he/she was a little too obviously and deliberately obtuse, to the point that I felt like the character was being made purposefully stupid in order to draw out the plot longer. There are lots of books where readers know more than the character about what's going on, and usually this serves to heighten the sense of worry and suspense over whether the character will figure everything out in time or not. In this case, I thought the "subtle" hints were way, way too obvious and that a character with the amount of average intelligence that Eon is presented to have should have been able to figure out the "mysteries" in the novel a little quicker. Or at least there should have been SOME connections being made. Instead, Eon would "notice" things in the narrative but completely fail to connect them with all the other things he/she had noticed before and therefore also fail to get some vague idea of what might possibly be going on.
Also, I felt some things weren't explained quite enough, and so when Eon made some of his/her decisions, they felt like they came absolutely out of nowhere. In this way, (SPOILERS) I thought the whole "drugs made them do it" thing was a bit of a cop-out - it left the character free to make even MORE illogical and unexplained decisions that the reader is supposed to just accept because "look guys, he/she is on drugs and can't think properly." These things were supposed to make me worry about the character, but they really just heightened my sense of frustrated apathy toward him/her, and increased my general sympathy toward the other characters for having to deal with all these drug addicts and crazy people.
As well, I thought there wasn't really a point to Eon having a busted hip. While it could have made the character look for strength and agency in ingenious ways, instead it tended to make him/her seem like dead weight getting pulled along by other people and frankly, pretty useless. And there was magical "you're cured" stuff that I thought really undermined the whole thing. Instead of it being a reward for his/her strength of character, it seemed more like just a resounding "yay, maybe he/she stop being so useless now." I thought the author could have let the injury be there, but still have given Eon some extra agency so he/she didn't just trail after people like a lost duckling half the time.
I might read Eona, just because I'm interested to see if I'll warm to the character more, though. Ultimately - interesting idea, although I wasn't personally a big fan of the execution. Again, though, other people might like Eon, and therefore really enjoy the book.